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ASUS Begins Enabling Limited PCIe Gen 4.0 on AMD 400-series Chipset Motherboards

ASUS believes that PCI-Express gen 4.0 support on older socket AM4 motherboards based on the AMD 400-series chipset is technically possible, even if discouraged by AMD. The company's latest series of motherboard BIOS updates that expose PCIe Gen 4 toggle in the PCIe settings, does in fact enable PCIe gen 4.0 to all devices that are directly wired to the SoC. These would be the PCI-Express x16 slots meant for graphics, and one of the M.2 slots that has PCIe x4 wiring to the SoC. Below is a list of motherboards scored by Chinese tech publication MyDrivers, which details the extent of PCIe gen 4.0 support across a number of ASUS motherboards based on the X470 and B450 chipsets.

AMD apparently did not explicitly block PCIe gen 4.0 for older chipsets. It merely suggested to motherboard manufacturers not to enable it, since the newer AMD 500-series motherboards are built to new PCB specifications that ensure PCIe gen 4.0 signal-integrity and stability. ASUS wants to leave it to users to decide if they want gen 4.0. If their machines are unstable, they can choose to limit PCIe version to gen 3.0 in their BIOS settings. Among other things, AMD's specifications for 500-series chipset motherboards prescribe PCBs with more than 4 layers, for optimal PCIe and memory wiring. Many of the motherboards on ASUS' list, such as the TUF B450 Pro Gaming, use simple 4-layer PCBs.

UL Releases PCI Express Feature Test For 3DMark Ahead of PCIe 4.0 Hardware

With PCI-Express 4.0 graphics cards and motherboards soon to arrive, UL has released their PCI Express feature test for 3DMark. This latest addition has been designed to verify the bandwidth available to the GPU over a computer's PCI Express interface. To accomplish this, the test will make bandwidth the limiting factor for performance and does so by uploading a large amount of vertex and texture data to the GPU for each frame. The end goal is to transfer enough data over the PCIe 4.0 interface to thoroughly saturate it. Once the test is complete, the end result will be a look at the average bandwidth achieved during the test.

PCI-SIG Announces PCIe 6.0 Specification

PCI-SIG today announced that PCI Express (PCIe ) 6.0 technology will double the data rate to 64 GT/s while maintaining backwards compatibility with previous generations and delivering power efficiency and cost-effective performance. The PCIe 6.0 specification is actively targeted for release in 2021.

PCIe 6.0 Specification Features
  • Delivers 64 GT/s raw bit rate and up to 256 GB/s via x16 configuration
  • Utilizes PAM-4 (Pulse Amplitude Modulation with 4 levels) encoding and leverages existing 56G PAM-4 in the industry
  • Includes low-latency Forward Error Correction (FEC) with additional mechanisms to improve bandwidth efficiency
  • Maintains backwards compatibility with all previous generations of PCIe technology

ASUS Unveils the Prime X299 Edition 30 and Prime Utopia Concept Desktop

ASUS is commemorating its 30th year in the motherboard industry with the Prime X299 Edition 30 motherboard and Prime Utopia reference desktop platform. The Prime X299 Edition 30 is a premium LGA2066 motherboard with support for Core i9-9000X series processors out of the box. It is based on a familiar-looking PCB layout, mated to a new mostly-white composite heatsink/shroud over the rear I/O, the M.2 slots, and the chipset heatsink. The VRM heatsink is active and has a concealed 40 mm spinner ventilating the metal. Three each of PCI-Express 3.0 x16 and M.2 NVMe slots, an integrated rear I/O shield, premium connectivity that includes 802.11ac WLAN, and a high-end onboard audio solution, make for the rest of it.

The Prime Utopia is something else. It's a concept high-end desktop built around a motherboard that has slots, headers, ports, and connectors on both sides of the PCB. Its "obverse side," if you can call it that, has a shroud that conceals the memory slots, most controllers, chipset, and a 7-inch USB display that puts out real-time system monitoring data, or pretty much anything you want it to display. The CPU socket is on the other side of the PCB, and the processor and CPU VRM are liquid-cooled. An angled PCI-Express slot holds the graphics card along the plane of the motherboard. It all comes together on a CM Cosmos-like chassis frame that lets you show the innards off.

AMD X570 Unofficial Platform Diagram Revealed, Chipset Puts out PCIe Gen 4

AMD X570 is the company's first in-house design socket AM4 motherboard chipset, with the X370 and X470 chipsets being originally designed by ASMedia. With the X570, AMD hopes to leverage new PCI-Express gen 4.0 connectivity of its Ryzen 3000 Zen2 "Matisse" processors. The desktop platform that combines a Ryzen 3000 series processor with X570 chipset is codenamed "Valhalla." A rough platform diagram like what you'd find in motherboard manuals surfaced on ChipHell, confirming several features. To maintain pin-compatibility with older generations of Ryzen processors, Ryzen 3000 has the same exact connectivity from the SoC except two key differences.

On the AM4 "Valhalla" platform, the SoC puts out a total of 28 PCI-Express gen 4.0 lanes. 16 of these are allocated to PEG (PCI-Express graphics), configurable through external switches and redrivers either as single x16, or two x8 slots. Besides 16 PEG lanes, 4 lanes are allocated to one M.2 NVMe slot. The remaining 4 lanes serve as the chipset bus. With X570 being rumored to support gen 4.0 at least upstream, the chipset bus bandwidth is expected to double to 64 Gbps. Since it's an SoC, the socket is also wired to LPCIO (SuperIO controller). The processor's integrated southbridge puts out two SATA 6 Gbps ports, one of which is switchable to the first M.2 slot; and four 5 Gbps USB 3.x ports. It also has an "Azalia" HD audio bus, so the motherboard's audio solution is directly wired to the SoC. Things get very interesting with the connectivity put out by the X570 chipset.
Update May 21st: There is also information on the X570 chipset's TDP.
Update May 23rd: HKEPC posted what looks like an official AMD slide with a nicer-looking platform map. It confirms that AMD is going full-tilt with PCIe gen 4, both as chipset bus, and as downstream PCIe connectivity.

BIOSTAR Racing X570GT8 Zen 2 Motherboard Pictured and Detailed

MSI, without naming its product, teased its MEG X570 Ace motherboard late last week, obeying the cardinal rules of a teaser, such as not putting out clear pictures or names. BIOSTAR probably wanted to do something similar, but ended up leaking glaring details and pictures of its flagship socket AM4 motherboard based on the AMD X570 chipset, the Racing X570GT8. The X570 is AMD's first in-house design chipset for the AM4 socket after "Promontory" and FM2-based "Bolton," supplied by ASMedia. It was necessitated by the need to get downstream PCIe connectivity from the chipset to be certified for the latest generations (gen 3.0 or later), by AMD, and overcome many of the connectivity limitations of ASMedia "Promontory," from which AMD carved out previous socket AM4 chipsets.

Design compulsions of being a flagship product aside, there are signs of a clear focus on strengthening the CPU VRM on the Racing X570GT8, to cope with the rumored Ryzen 9 series 16-core "Zen 2" processor. The board draws power from a combination of 24-pin ATX and 8+4 pin EPS connectors, conditioning it for the processor with a 12-phase VRM. There are two metal-reinforced PCI-Express x16 slots wired to the AM4 SoC, and we get the first glimpse of the PCI-Express gen 4.0 lane switching and re-driver circuitry. We haven't seen anything to suggest that the downstream PCIe lanes from the X570 chipset are gen 4.0, yet, but we expect them to at least be gen 3.0. The presence of three M.2 slots bodes well for the downstream PCIe lane count. ASMedia "Promontory" puts out a paltry eight gen 2.0 lanes. It's also interesting to see an active fan-heatsink cooling the X570 chipset, indicating a rather high TDP compared to the 3-5 Watt TDP of the 400-series "Promontory" low-power variant chipsets. The component choices by BIOSTAR look premium and are a callback to its T-Power glory days enthusiasts remember.

AMD Ryzen 3000 "Zen 2" BIOS Analysis Reveals New Options for Overclocking & Tweaking

AMD will launch its 3rd generation Ryzen 3000 Socket AM4 desktop processors in 2019, with a product unveiling expected mid-year, likely on the sidelines of Computex 2019. AMD is keeping its promise of making these chips backwards compatible with existing Socket AM4 motherboards. To that effect, motherboard vendors such as ASUS and MSI began rolling out BIOS updates with AGESA-Combo 0.0.7.x microcode, which adds initial support for the platform to run and validate engineering samples of the upcoming "Zen 2" chips.

At CES 2019, AMD unveiled more technical details and a prototype of a 3rd generation Ryzen socket AM4 processor. The company confirmed that it will implement a multi-chip module (MCM) design even for their mainstream-desktop processor, in which it will use one or two 7 nm "Zen 2" CPU core chiplets, which talk to a 14 nm I/O controller die over Infinity Fabric. The two biggest components of the IO die are the PCI-Express root complex, and the all-important dual-channel DDR4 memory controller. We bring you never before reported details of this memory controller.

AMD Unveils "Zen 2" CPU Architecture and 7 nm Vega Radeon Instinct MI60 at New Horizon

AMD today held its "New Horizon" event for investors, offering guidance and "color" on what the company's near-future could look like. At the event, the company formally launched its Radeon Instinct MI60 GPU-based compute accelerator; and disclosed a few interesting tidbits on its next-generation "Zen 2" mircroarchitecture. The Instinct MI60 is the world's first GPU built on the 7 nanometer silicon fabrication process, and among the first commercially available products built on 7 nm. "Rome" is on track to becoming the first 7 nm processor, and is based on the Zen 2 architecture.

The Radeon Instinct MI60 is based on a 7 nm rendition of the "Vega" architecture. It is not an optical shrink of "Vega 10," and could have more number-crunching machinery, and an HBM2 memory interface that's twice as wide that can hold double the memory. It also features on-die logic that gives it hardware virtualization, which could be a boon for cloud-computing providers.

AMD Could Solve Memory Bottlenecks of its MCM CPUs by Disintegrating the Northbridge

AMD sprung back to competitiveness in the datacenter market with its EPYC enterprise processors, which are multi-chip modules of up to four 8-core dies. Each die has its own integrated northbridge, which controls 2-channel DDR4 memory, and a 32-lane PCI-Express gen 3.0 root complex. In applications that can not only utilize more cores, but also that are memory bandwidth intensive, this approach to non-localized memory presents design bottlenecks. The Ryzen Threadripper WX family highlights many of these bottlenecks, where video encoding benchmarks that are memory-intensive see performance drops as dies without direct access to I/O are starved of memory bandwidth. AMD's solution to this problem is by designing CPU dies with a disabled northbridge (the part of the die with memory controllers and PCIe root complex). This solution could be implemented in its upcoming 2nd generation EPYC processors, codenamed "Rome."

With its "Zen 2" generation, AMD could develop CPU dies in which the integrated northrbidge can be completely disabled (just like the "compute dies" on Threadripper WX processors, which don't have direct memory/PCIe access relying entirely on InfinityFabric). These dies talk to an external die called "System Controller" over a broader InfinityFabric interface. AMD's next-generation MCMs could see a centralized System Controller die that's surrounded by CPU dies, which could all be sitting on a silicon interposer, the same kind found on "Vega 10" and "Fiji" GPUs. An interposer is a silicon die that facilitates high-density microscopic wiring between dies in an MCM. These explosive speculative details and more were put out by Singapore-based @chiakokhua, aka The Retired Engineer, a retired VLSI engineer, who drew block diagrams himself.

SilverStone ECM23 is an M.2 Riser+Heatsink Letting You Slot-in Your Drives Like Cartridges

The ECM23 from SilverStone is one of the more interesting M.2-PCIe SSD risers to come out in recent times. It looks like a game cartridge from 1980s, and slots into one of your PCI-Express x16 slots, which it then uses to wire out an M.2-2280 M-key slot with PCIe x4 wiring. The riser itself has x16 interface, but beyond x4, all the other lanes are blank, and only serve to add retention, since the riser doesn't feature an add-on card bracket to hold it in place. The main PCB has no logic of its own, other than link/activity LEDs for the four PCIe lanes.

It's more optimal to use drives with all their hot components on one side, since that side has access to the chunky ~40 g main heatsink. Heat from the other side is drawn from a copper mesh printed on the PCB, which supposedly conveys it to the back side, which has an aluminium back-plate, which bolts onto the main heatsink, sandwiching the PCB and drive in the middle. Measuring 105 mm (W) x 11 mm (H) x 44 mm (D), the ECM23 weighs 52 g (excluding the weight of your drive). The company didn't reveal pricing.

Intel Starts Producing 3D QLC NAND Flash Based PCIe SSDs for Data-Centers

Intel announced that it started mass-production of PCI-Express SSDs for data-centers that implement the latest-generation 3D QLC NAND flash memory. The new QLC (4 bits per cell) NAND flash memory enables 33% increases in densities over TLC NAND flash, and with 3D (stacks), the density per chip is further multiplied. Built in the 15 mm-thick 2.5-inch form-factor with U.2 interface, the drive is built for the rigors of "warm storage" (data that isn't hot, but isn't cold/archival, either). Such drives can be slower than "hot data" drives based on faster MLC or even SLC NAND flash, but almost always up; and faster than HDDs. The first 3D QLC NAND-based SSD, which probably uses the same chips as this drive, is the Micron 5210 ION, which was launched in May.

Thermalright Intros Silver Arrow TR4 CPU Cooler

Thermalright today introduced a variant of its Silver Arrow dual fin-stack, tower-type CPU cooler for AMD socket TR4, meant for Ryzen Threadripper processors. Capable of handling thermal loads of up to 320W, the cooler can be paired with even upcoming 250W TDP 24-core and 32-core Threadripper II models. Although bearing the same name, the Silver Arrow TR4 bears little design resemblance with the Silver Arrow ITX-R or the Silver Arrow SB-E, or even the original Silver Arrow from 2010. It's the largest cooler of this class, with an enlarged nickel-plated copper base designed to provide full coverage of the Threadripper IHS, from which eight 6 mm-thick heat pipes draw heat, with the two aluminium fin-stacks propagating along their ends.

Nested between the two fin-stacks is a 140 mm fan which takes in 4-pin PWM input, spins between 600 to 2,500 RPM, pushing 53.3 - 220.9 m³/h, with a noise output ranging between 21 - 45 dBA. With its fan in place, the Silver Arrow TR4 measures 155 mm x 103 mm x 163 mm (LxWxH). The narrow width ensures clearance for the memory slots that flank the CPU socket from either side. The fin-stack itself is offset sideways to ensure clearance for the topmost PCI-Express slot on your motherboard. You can latch on two additional fans. A syringe of Thermalright's Chill Factor III TIM comes included. The cooler tips the scales at 1,050 g. The company didn't reveal pricing.

AMD Vega 20 GPU Could Implement PCI-Express gen 4.0

The "Vega 20" silicon will be significantly different from the "Vega 10" which powers the company's current Radeon RX Vega series. AMD CEO Dr. Lisa Su unveiled the "Vega 20" silicon at the company's 2018 Computex event, revealing that the multi-chip module's 7 nm GPU die is surrounded by not two, but four HBM2 memory stacks, making up to 32 GB of memory. Another key specification is emerging thanks to the sharp eyes at ComputerBase.de - system bus.

A close inspection of the latest AMDGPU Linux driver includes PCI-Express link speed definitions for PCI-Express gen 4.0, which offers 256 Gbps of bandwidth per direction at x16 bus width, double that of PCI-Express gen 3.0. "Vega 20" got its first PCIe gen 4.0 support confirmation from a leak slide that surfaced around CES 2018. AMD "Vega" architecture slides from last year hinted at a Q3/Q4 launch of the first "Vega 20" based product. The same slide also hinted that the next-generation EPYC processor, which we know are "Zen 2" based and not "Zen+," could feature PCI-Express gen 4.0 root-complexes. Since EPYC chips are multi-chip modules, it could also hint at the likelihood of PCIe gen 4.0 on "Zen 2" based 3rd generation Ryzen processor family.

COLORFUL Adds Two CN600S Solid-State Drives to Their Storage Offerings

COLORFUL Technology Company Limited, professional manufacturer of graphics cards, motherboards and high-performance storage solutions is proud to announce the addition of two new options for its CN600S line of solid-state drives. COLORFUL is adding the CN600S 240GB and CN600S 480GB drives featuring Intel 64-layer 3D NAND. Those looking for a cost-effective high-performance, high-capacity storage solution for low-profile applications including notebooks and other M.2 capable devices. The improved speed and capacity of the COLORFUL CN600S allows it to be used in a wider range of applications including gaming, professional use or HTPC.

The COLORUL CN600S is equipped with the SMI 2263XT controller, features a M.2 2280 design standard and is rated for transfer speeds up to 2 GB/s reads and 1.5 GB/s write performance. The SMI 2263XT uses the PCIe Gen3 x4 interface and can deliver 4x faster performance than SATA3 for reading, accessing and opening applications and games. The COLORFUL CN600 M.2 PCIe SSD is focused in offering the most compelling cost-benefit ratio in the market.

Colorful Working on AMD 400-series Chipset AM4 Motherboards

Colorful is designing its first socket AM4 motherboards, according to industry sources. The company will release its first socket AM4 motherboards after the 2018 Computex Expo (June). These boards will be based on AMD 400-series chipsets, and will come with out of the box support for Ryzen "Pinnacle Ridge" processors, Ryzen "Raven Ridge" APUs, and existing Ryzen "Summit Ridge" processors. Taking advantage of PCI-Express gen 3.0 general-purpose connectivity of the 400-series chipset, the boards will feature multiple 32 Gbps NVMe interfaces (M.2 or U.2). It's possible that the company could attach its coveted iGame Vulcan brand to some of these models. The company currently only sells motherboards for Intel platforms. Its lineup includes motherboards based on Intel Z370 and X299 chipsets, including crypto-currency miner-centric boards based on lesser Intel chipsets, such as the B250. AMD is expected to debut its 400-series chipset alongside its 2nd generation Ryzen "Pinnacle Ridge" processors, in Q2-2018.

Colorful Intros Unique C.J1900A-BTC PLUS V20 Mining Motherboard

Colorful today introduced the uniquely designed C.J1900A-BTC PLUS V20 motherboard for mining rigs. This odd-ball form-factor board is designed for makeshift racks, and removes the need for PCIe riser cables. The board itself is a large PCB with nine PCI-Express x16 slots with 1-slot spacing, of which eight can be used for installing your mining graphics cards (x1 wiring), while the slot on the middle (blue), isn't really a PCI-Express slot.

The blue slot has custom wiring for the business end of the motherboard, a riser card which houses the Celeron J1900 SoC, a DDR4 SO-DIMM slot, an mSATA 6 Gb/s slot for your SSD, and the board's main connectivity, which includes two USB 2.0 ports, two gigabit Ethernet interfaces, and an HDMI display output. If you have trouble finding an mSATA SSD in 2017, there's also a standard SATA 6 Gb/s port. The riser draws power from a 4-pin ATX input. The main PCB has eight 6-pin PCIe power inputs, which wire out to 6-pin PCIe outputs near each black slot. This is more of a cable-management feature, smaller (20 cm long) male-to-male 6-pin PCIe cables connect the outputs to the graphics cards.

PCI SIG Releases PCI-Express Gen 4.0 Specifications

The Peripheral Component Interconnect (PCI) special interest group (SIG) published the first official specification (version 1.0) of PCI-Express gen 4.0 bus. The specification's previous draft 0.9 was under technical review by members of the SIG. The new generation PCIe comes with double the bandwidth of PCI-Express gen 3.0, reduced latency, lane margining, and I/O virtualization capabilities. With the specification published, one can expect end-user products implementing it. PCI SIG has now turned its attention to the even newer PCI-Express gen 5.0 specification, which will be close to ready by mid-2019.

PCI-Express gen 4.0 comes with 16 GT/s bandwidth per-lane, per-direction, which is double that of gen 3.0. An M.2 NVMe drive implementing it, for example, will have 64 Gbps of interface bandwidth at its disposal. The SIG has also been steered toward lowering the latencies of the interconnect as HPC hardware designers are turning toward alternatives such as NVLink and InfinityFabric, not primarily for the bandwidth, but the lower latency. Lane margining is a new feature that allows hardware to maintain a uniform physical layer signal clarity across multiple PCIe devices connected to a common root complex. This is particularly important when you have multiple pieces of mission-critical hardware (such as RAID HBAs or HPC accelerators), and require uniform performance across them. The new specification also adds new I/O virtualization features that should prove useful in HPC and cloud computing.

AMD Reveals Ryzen 7 Family, Pricing, and Radeon Vega Logo

At a press event by AMD, company CEO Lisa Su unveiled the first three AMD Ryzen desktop processor models, the top-dog Ryzen 7-1800X, the Ryzen 7-1700X, and the Ryzen 7-1700. The R7-1800X is priced at USD $499, followed by the R7-1700X at $399, and the R7-1700 at $329. The three chips will be available for purchase on the 2nd of March, 2017. The R7-1800X is clocked at 3.60 GHz, with a TurboCore frequency of 4.00 GHz, and the XFR (extended frequency range) feature, which further overclocks the chip, depending on the effectiveness of your CPU cooler.

The Ryzen 7-1700X ships with 3.40 GHz clocks, with 3.80 GHz TurboCore frequency, and the XFR feature. The Ryzen 7-1700 lacks XFR, and comes with slightly lower clocks, at 3.00 GHz core, and 3.70 GHz TurboCore. All three are true 8-core chips, with 512 KB of dedicated L2 cache per core, and 16 MB of shared L3 cache. Also featured are dual-channel DDR4 integrated memory controllers, and an integrated PCI-Express gen 3.0 root complex. The Ryzen 7-1700 has a TDP of just 65W (for a performance 8-core chip that's a kick in the butts of Intel's engineers), and will include an AMD Wraith Max cooling solution, while the 1700X and 1800X have TDP rated at 95W, and will come without coolers. At its media event, CEO Lisa Su stated that at $499, the Ryzen 7-1800X "smokes" the Intel Core i7-6900K eight-core processor. The company also unveiled the branding of its Radeon Vega enthusiast graphics family. Lastly, feast your eyes on the beautiful, 14 nm, Made-in-USA die-shot of Ryzen.

DeepCool Shows Off its QuadStellar Chassis

Building on the legacy of its TriStellar series cases, DeepCool unveiled the bigger, four-lobed QuadStellar chassis. Unlike the TriStellar, which housed mini-ITX motherboards, the QuadStellar is much larger, and designed for full-fledged ATX motherboards. The central axis to the four lobes is more functional than it is on the TriStellar, as two opposing lobes can now meet in the middle to make up a large continuous chamber to house the ATX motherboard, and its 8 expansion slots. One of the other two lobes houses the PSU bay with a few drive bays; while the other lobe has three additional PCI-Express x16 slot risers, and a few more drive bays. The case measures 523 mm x 485 mm x 485 mm. It features nine 3.5-inch and twelve 2.5-inch drive bays. DeepCool plans to launch this case by May 2017.

ASUS Prime B250M-Plus Pictured, Too

The third Prime B250 series motherboard by ASUS is the B250M-Plus. This micro-ATX motherboard offers most of the features its bigger siblings ship with. The board features the same 7-phase VRM as the other boards. Expansion slots include one each of PCI-Express 3.0 x16, PCIe x1, and legacy PCI. Storage connectivity includes one 32 Gb/s M.2 slot, and six SATA 6 Gb/s ports. The board offers 8-channel HD audio (compared to 6-channel on the larger boards), gigabit Ethernet, USB 3.0 ports, and display outputs that include HDMI, DVI, and D-Sub. Expect a sub-$100 price.

AMD Reveals Three Entries on the WX Series Lineup: WX4100, WX5100 and WX7100

At its WX call, AMD focused on shifts in creativity from traditional design flows such as Solidworks, Adobe and Autodesk towards game engines as solutions for design visualization (Unreal Engine, Unity, CryEngine, or Autodesk's own Stingray platform), which signal changes in the creator ecosystem. Thanks to globalization, the Internet, and the available wealth of knowledge one can access through it, the line between amateurs and professionals is becoming more and more blurred. Now, those who would once be called amateurs are also using professional tools, and AMD plans to be at the forefront of technologies empowering creators to deliver their vision.

Radeon PRO serves to give creators more flexible and powerful solutions, leveraging open-source resources and centering the ecosystem back on creators and the tools they choose to use, with focused support on VR. As such, AMD is giving them the tools they need, by introducing three new products featuring the Polaris architecture, including 3 year standard + 7 year free extended warranty (including components such as the PCB itself, the PCI-Express slot, and the heatsinks), with AMD taking that extra 7 years as company commitment towards the quality of their products. Those three products are the WX4100, the WX5100, and the WX7100, and have planned, staggered availability throughout November.

PCI-Express 4.0 Pushes 16 GT/s per Lane, 300W Slot Power

The PCI-Express gen 4.0 specification promises to deliver a huge leap in host bus bandwidth and power-delivery for add-on cards. According to its latest draft, the specification prescribes a bandwidth of 16 GT/s per lane, double that of the 8 GT/s of the current PCI-Express gen 3.0 specification. The 16 GT/s per lane bandwidth translates into 1.97 GB/s for x1 devices, 7.87 GB/s for x4, 15.75 GB/s for x8, and 31.5 GB/s for x16 devices.

More importantly, it prescribes a quadrupling of power-delivery from the slot. A PCIe gen 4.0 slot should be able to deliver 300W of power (against 75W from PCIe gen 3.0 slots). This should eventually eliminate the need for additional power connectors on graphics cards with power-draw under 300W, however, the change could be gradual, as graphics card designers could want to retain backwards-compatibility with older PCIe slots, and retain additional power connectors. The PCI-SIG, the special interest group behind PCIe, said that it would finalize the gen 4.0 specification by the end of 2016.

High PCIe Slot Power Draw Costs RX 480 PCI-SIG Integrator Listing

AMD's design of the Radeon RX 480 graphics card, which draws over 75W of power from the PCI-Express x16 slot, has cost it a product listing on the PCI-SIG Integrators List. The list is compiled for hardware devices implementing the various PCI-Express specifications to the letter. The RX 480 is off-spec, in that it overdraws power from the slot, as the card needs more power than what the slot and the 6-pin PCIe power connector can provide while staying within specs. According to these specs, the slot can provide up to 75W of power, and the 6-pin connector another 75W. The RX 480 was tested to draw more than this 150W power budget.

What this means for AMD is that it cannot display the PCI-Express certification logo on the product or its marketing materials. This, however, may not affect AMD's add-in board (AIB) partners that are PCI-SIG members in their own right, and make graphics cards with their own sub-vendor IDs, provided their power-supply designs comply with PCIe specs. Custom-design cards with an 8-pin PCIe power connector, instead of 6-pin, may qualify as the combination of the 8-pin connector and the slot yields a power budget of 225W. AMD released a software fix to the issue of the cards overdrawing power from the slot, with the Radeon Software Crimson Edition 16.7.1 Beta.

AMD Releases PCI-Express Power Draw Fix, We Tested, Confirmed, Works

Earlier today, AMD has posted a new Radeon Crimson Edition Beta, 16.7.1, which actually includes two fixes for the reported PCI-Express overcurrent issue that kept Internet people busy the last days.

The driver changelog mentions the following: "Radeon RX 480's power distribution has been improved for AMD reference boards, lowering the current drawn from the PCIe bus", and there's also a second item "A new "compatibility mode" UI toggle has been made available in the Global Settings menu of Radeon Settings. This option is designed to reduce total power with minimal performance impact if end users experience any further issues."

Official Statement from AMD on the PCI-Express Overcurrent Issue

AMD sent us this statement in response to growing concern among our readers that the Radeon RX 480 graphics card violates PCI-Express power specification, by overdrawing power from its single 6-pin PCIe power connector and the PCI-Express slot. Combined, the total power budged of the card should be 150W, however, it was found to draw well over that power limit.

AMD has had out-of-spec power designs in the past with the Radeon R9 295X2, for example, but that card is targeted at buyers with reasonably good PSUs. The RX 480's target audience could face troubles powering the card. Below is AMD's statement on the matter. The company stated that it's working on a driver update that could cap the power at 150W. It will be interesting to see how that power-limit affects performance.
"As you know, we continuously tune our GPUs in order to maximize their performance within their given power envelopes and the speed of the memory interface, which in this case is an unprecedented 8 Gbps for GDDR5. Recently, we identified select scenarios where the tuning of some RX 480 boards was not optimal. Fortunately, we can adjust the GPU's tuning via software in order to resolve this issue. We are already testing a driver that implements a fix, and we will provide an update to the community on our progress on Tuesday (July 5, 2016)."
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