• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

Shortage of PEX8747 Bridge Chip Disturbs Various Launch Schedules

btarunr

Editor & Senior Moderator
Staff member
Joined
Oct 9, 2007
Messages
46,201 (7.69/day)
Location
Hyderabad, India
System Name RBMK-1000
Processor AMD Ryzen 7 5700G
Motherboard ASUS ROG Strix B450-E Gaming
Cooling DeepCool Gammax L240 V2
Memory 2x 8GB G.Skill Sniper X
Video Card(s) Palit GeForce RTX 2080 SUPER GameRock
Storage Western Digital Black NVMe 512GB
Display(s) BenQ 1440p 60 Hz 27-inch
Case Corsair Carbide 100R
Audio Device(s) ASUS SupremeFX S1220A
Power Supply Cooler Master MWE Gold 650W
Mouse ASUS ROG Strix Impact
Keyboard Gamdias Hermes E2
Software Windows 11 Pro
An increasing number of high-end graphics cards and motherboards are relying on PCI-Express bridge chips to expand the PCI-Express lane budgets, no thanks to the puny number of PCI-Express lanes today's mainstream computing platforms come with. Following the transition to PCI-Express Gen 3.0, with Intel's new platforms (Ivy Bridge and Sandy Bridge-E HEDT), there is a demand for Gen 3.0-compliant PCIe switching hardware, especially x48 bridge chips (which take in a PCI-Express x16 link, giving out two x16 links or four x8 links). Such chips are used on high-end motherboards to expand the number of PCIe slots, and on dual-GPU graphics cards.

It appears like NVIDIA does not have a PCIe Gen 3.0-compliant bridge chip of its own, and so the only company with one, is PLX Technology, with its PEX8747. The chip has been used on a variety of high-end motherboards, and NVIDIA's GeForce GTX 690 dual-GPU graphics card. PLX reportedly saw high demand, which resulted in several companies bagging initial allocations of the chip, leaving others out to dry, with the part being listed as out-of-stock by its maker. Newer clients of the chip will have to wait until PLX undertakes the next big production cycle, to get their allocations of the chip.



Casualties of shortage of the PEX8747 include the launch of AMD's ambitious Radeon HD 7990 dual-GPU graphics card, the various "HD 7970 X2" graphics cards, and high-end motherboards (eg: ASUS' Maximus V Extreme). NVIDIA's GTX 690 itself isn't readily found, either, and we are hard pressed to buy the "high-demand" argument that has been used to explain GTX 680 shortages, and to good effect, considering the GTX 690's scorching $999-$1299 end-user price.

At Computex, we spoke with some of the graphics card vendors with so-called HD 7970 X2 models in the works. We learned through our conversations that some of them are hit by the shortage of PEX8747, which destabilized their product launch schedules, and that they are looking for "alternatives." These could include PCI-Express Gen 2.0 switches, which could hurt the products' specification sheets unless the companies balance it with [relatively] attractive pricing (at their expense of their margins).

If AMD is banking on dual-GPU graphics cards such as the HD 7990 to restore competitiveness of its high-end lineup, now would be a good time to invest in development of a PCI-Express 3.0 bridge chip of its own. We know it has the chops to do so, being a motherboard chipset designer. The chip could then be implemented on upcoming, as well as future generations of dual-GPU Radeon graphics cards.

With inputs from Hardware.fr.

View at TechPowerUp Main Site
 
Last edited:
Joined
Dec 4, 2010
Messages
61 (0.01/day)
Processor Intel i5 3570K @ 4.4GHz
Motherboard Asus Maximus V Gene
Cooling Be Quiet Dark Rock Advanced
Memory 8GB Samsung Green@ 220Mhz 10-11-10-28 T1 1.55v
Video Card(s) Nvidia Geforce GTX460 768MB 850Mhz/1999Mhz
Storage OCZ Vertex 3 120GB + lots of other drives
Display(s) 27" AOC e2795Vh
Case Bitfenix Shinodi
Power Supply Corsair GS 800W
Software Windows 7 64bit
Joined
Oct 9, 2009
Messages
716 (0.14/day)
Location
Finland
System Name RGB-PC v2.0
Processor AMD Ryzen 7950X
Motherboard Asus Crosshair X670E Extreme
Cooling Corsair iCUE H150i RGB PRO XT
Memory 4x16GB DDR5-5200 CL36 G.SKILL Trident Z5 NEO RGB
Video Card(s) Asus Strix RTX 2080 Ti
Storage 2x2TB Samsung 980 PRO
Display(s) Acer Nitro XV273K 27" 4K 120Hz (G-SYNC compatible)
Case Lian Li O11 Dynamic EVO
Audio Device(s) Audioquest Dragon Red + Sennheiser HD 650
Power Supply Asus Thor II 1000W + Cablemod ModMesh Pro sleeved cables
Mouse Logitech G500s
Keyboard Corsair K70 RGB with low profile red cherrys
Software Windows 11 Pro 64-bit
Probably also one of the many reasons why there is no HD 7990 yet.
 

the54thvoid

Intoxicated Moderator
Staff member
Joined
Dec 14, 2009
Messages
12,344 (2.37/day)
Location
Glasgow - home of formal profanity
Processor Ryzen 7800X3D
Motherboard MSI MAG Mortar B650 (wifi)
Cooling be quiet! Dark Rock Pro 4
Memory 32GB Kingston Fury
Video Card(s) Gainward RTX4070ti
Storage Seagate FireCuda 530 M.2 1TB / Samsumg 960 Pro M.2 512Gb
Display(s) LG 32" 165Hz 1440p GSYNC
Case Asus Prime AP201
Audio Device(s) On Board
Power Supply be quiet! Pure POwer M12 850w Gold (ATX3.0)
Software W10
Probably also one of the many reasons why there is no HD 7990 yet.

That makes sense - another source (S|A) stated the delay in the 7990 was in part down to waiting for higher binned Tahiti's (Tahiti 2) and another non-AMD specific issue. Could well be these chips.
 
Joined
Aug 13, 2010
Messages
5,369 (1.08/day)
I already got mine
 
Joined
May 22, 2010
Messages
2,516 (0.50/day)
Location
Canada
System Name m1dg3t | DeathBox | HairPi 3
Processor 3570k @ 4.0 1.15v BIOS | q9550 @ 3.77 1.325v BIOS
Motherboard Asrock z77e iTX | p5q Dlx 2301 BIOS
Cooling Custom Water | D-14 & HR-03gt | Passive HSF
Memory Samsung MV-3V4G3D 4g x 2 @ 1866 1.35v | OcZ RpR 2g x 4 @ 1067 2.2v
Video Card(s) MSi 7950 tf3 @1000 / 1350 | Asus 5870 V2 @ 900 / 1275
Storage Adata sx900 256Gb / WD 2500 HHTZ | WD 1001 FALS x 2
Display(s) BenQ gw2750hm | 46" Sharp Quatron
Case BitFenix Prodigy - m0dd3d | Antec Fusion Remote MAX
Audio Device(s) Onboard Toslink > Yamaha HTR 6290 | Xonar HDAV1.3 > Yamaha DSP z7
Power Supply Ocz mXp700w | Ocz zx850w | Cannakit 5v 2.5a
Mouse Logitech G700s | Logitech G9x - Cable Repaired
Keyboard TT Meka G1 - Black w Cherry Blacks| Logitech G11
Software Win7 Home | Xp sp3 & Vista ultimate | Raspbian
Benchmark Scores Epeen!! Who needs epeen??
Guess this was Nvidias way of getting back at ATi/AMD for snatching up all the 28mm wafers a few month's back? :confused: :rolleyes: :laugh:

With all the intelligence/money these companies have you think they would spend a few minutes thinking about things before saying "Here you go". :rolleyes: :eek: My/our purchase $$$ is NOT your R & D $$$. R & D should be done/completed BEFORE release to public :cool:

But if that were true, i (and many others), wouldn't be stuck with pieces of hardware that have never functioned as advertised.

My case in point is my Xonar HDAV 1.3. Never worked properly since day 1. Sent it in for RMA at MY EXPENSE and came back still not working. Asus sent me a replacement card and it still doesn't work. Have spoke to a handfull of people at Asus and they have no idea what a soundcard even is to begin with! Let alone be of any use in trouble shooting the issue. All due to software from what i can gather and they pulled it from their catalogue so it's my special headache now :cry:

/Rant

I have 2 Xonar HDAV 1.3's with upgraded firmware if anyone is interested? :roll:
 
Top