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BIOSTAR Formally Enables PCIe Gen 4 on its AMD 400-series Motherboards

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BIOSTAR formally (officially) enabled PCI-Express gen 4.0 support for four of its socket AM4 motherboard models based on the AMD X470 and B450 chipsets, through BIOS updates. The updated BIOS lets you use PCI-Express gen 4.0 graphics cards on the topmost PCI-Express x16 slot, and the M.2 NVMe slot that's directly wired to the AM4 SoC. The expansion slots that are wired to the chipset are still restricted to PCIe gen 2.0. You will need a 3rd generation Ryzen "Matisse" processor for PCI-Express gen 4.0. Among the motherboards that receive PCIe gen 4.0 support through BIOS updates are the AB45C-M4S (B450MH), the AB35G-M4S (B45M2), the AX47A-A4T (X470GT8), and the AX47A-I4S (X470GTN). The links lead to the BIOS image files on BIOSTAR website, which you use at your own risk.



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Great for the motherboard owners, but i dont think amd is to happy about this as they stated pcie gen 4 cut not work on 400 series chipsæt/boards. As far i understand gen 4 support is limited to one pci espress slot and one m.2 slot. At least that seems to be the case with asus boards as only the cpu has pcie gen 4 lanes and thats why only those two things can run gen 4 while the rest will still only run pcie gen 3.

And with al ready Asus and Biostar out with boards that can do it. I think it's just a matter of time before we see other manufactores join's in on it. Unless amd active goes out and say, this is not alright and maybe it would have some sort of a punishment like amd cut stop working with a manufactor or something like it.
 
I wonder what AMD will say about this...
 
Great for the motherboard owners, but i dont think amd is to happy about this as they stated pcie gen 4 cut not work on 400 series chipsæt/boards. As far i understand gen 4 support is limited to one pci espress slot and one m.2 slot. At least that seems to be the case with asus boards as only the cpu has pcie gen 4 lanes and thats why only those two things can run gen 4 while the rest will still only run pcie gen 3.

And with al ready Asus and Biostar out with boards that can do it. I think it's just a matter of time before we see other manufactores join's in on it. Unless amd active goes out and say, this is not alright and maybe it would have some sort of a punishment like amd cut stop working with a manufactor or something like it.

Edit: after reading deeper in the news i see that limit also goes for biostar, so that properly goes for all motherboards then that can run pcie gen 4 stable.

I wonder what AMD will say about this...

Me two. I dont think they are to happy about it. It seems like amd doing an intel this time. Meaning intel said the 9000 series cpu cut not work on older chipsæt motherboards and yet some people got them to work by modifying bios and now amd pulling a stunt with pcie gen 4 on 400 series motherboards al throw it's only limited support.
 
AMD never promised it would work on older boards.
Besides, this could cause data loss if the board is a borderline case.
I think this was a responsible thing to do, as devices have to pass certification for PCIe. If you don't meet the strict standards, then you don't pass, there are no borderline cases.
 
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I have to say all of this (BIOS ROM limitations, new MAX motherboards with larger chips, CPU's not being supported anymore, RAID support going and then coming back, PCIEx-4 only on X570 then also on older mobos) is very confusion and I feel it shows a lack of communication between AMD and their partners - or even worse, some incompetence in planning all of this.

THAT BEING SAID, it is nice to see AMD and partners trying to give existing users the best they can. For so many years Intel could not be bothered and just changed the chipset at every generation - that's easier, no need to plan, no need to communicate.
 
This is very good news, it means others will likely follow if not then they will lose sales to biostar ehhe
 
"i dont think amd is to happy about this as they stated pcie gen 4 cut not work on 400 series chipsæt/boards "
They never said that. They said they couldn't guarantuee PCIe 4.0 running on every older chipset out there and didn't want the confusion of some motherboard supporting it on B450 while another B450 or even X470 not supporting it. These half-truths are how fake news get spawned.

AMD as quoted by Anandtech:
"Pre-X570 boards will not support PCIe Gen 4. There's no guarantee that older motherboards can reliably run the more stringent signaling requirements of Gen4, and we simply cannot have a mix of "yes, no, maybe" in the market for all the older motherboards. The potential for confusion is too high. When final BIOSes are released for 3rd Gen Ryzen (AGESA 1000+), Gen4 will not be an option anymore. We wish we could've enabled this backwards, but the risk is too great."

Edit: And AMDs response so far has been (roughly) "we will remove this feature from future AGESA versions, so unless you want to stick with the outdated AGESA, you won't get PCIe 4.0 on old generation chipsets". We'll see who ultimately wins this battle.
 
PCI-e 4 need updated hardware which cannot be obtained by mere software update. Or you can really download updated PCI-e like RAM.
 
PCI-e 4 need updated hardware which cannot be obtained by mere software update. Or you can really download updated PCI-e like RAM.

Yes, the updated hardware is the Ryzen 3000 CPU. That's why only slots directly connected to it can get PCIe 4.0 and not others which go through the chipset.
 
Hmm, i was like 570x is a dealbraker in price, this kinda puts it back in play for me to get AMD.
i would be satisfied with 1 lane pcie-4.
 
Yes, the updated hardware is the Ryzen 3000 CPU. That's why only slots directly connected to it can get PCIe 4.0 and not others which go through the chipset.
PCI-e 4.0 needs new wiring, which cannot be obtained simply by updating firmware.
The GPU's support new standard, then why we need new cable for new Display Port or HDMI standard?? Cause new standard has new requirement that old cable dont support. Like this new PCI-e need new wiring in PCB, old wiring were designed PCI-e 3.0 in mind not PCI-e 4.
 
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PCI-e 4.0 needs new wiring, which cannot be obtained simply by updating firmware.
The GPU's support new standard, then why we need new cable for new Display Port or HDMI standard?? Cause new saandard has new requirement that old cable dont support. Like this new PCI-e need new wiring in PCB, old wiring were designed PCI-e 3.0 in mind not PCI-e 4.

Absolutely. But Biostar make motherboards. If they decided to support PCI-ex 4 on their end, I would like to think that their engineering department evaluated the subject and approved it. Some standards can be compatible, we don't necessarily need new hardware for each new different standard.
 
Will be interesting to see what AMD says about this. Seems the mobo makers are throwing up a big middle finger at AMD over this. :p
 
I like options for PCIe4 that don't require active cooling.

I think situation will be more like, enabled in SW PCIe 4, like that you can read in your HW info that your mobo has PCIe 4. On paper.

In reality, it wont achieve bandwith, simply cause its physically impossible. And also for real bandwith of PCIe 4 it would require heavy cooling (cause older process used for chipsets).

Only thing that will happen is that line in best case scenario will run on physical limit, worst case, it just burns out.
 
In reality, it wont achieve bandwith, simply cause its physically impossible. And also for real bandwith of PCIe 4 it would require heavy cooling (cause older process used for chipsets).

It's only physically impossible sometimes though. If the trace lengths on the motherboard are short enough and properly laid out than Gen4 bandwidth would work from the CPU. It wasn't about having a special chipset to enable Gen4, it was about signal integrity over the currently available board designs. Some vendors fit the bill, some didn't. Biostar apparently tested and says their boards fit the requirements.
 
I think situation will be more like, enabled in SW PCIe 4, like that you can read in your HW info that your mobo has PCIe 4. On paper.

In reality, it wont achieve bandwith, simply cause its physically impossible. And also for real bandwith of PCIe 4 it would require heavy cooling (cause older process used for chipsets).

Only thing that will happen is that line in best case scenario will run on physical limit, worst case, it just burns out.

Sorry, but you're mixing things up here. This has nothing to do with the chipset or cooling.
As pointed out above, this is about trace length, but in addition to that, also about signal integrity and noise.
Regardless, even if these three are met, the older boards won't reach full PCIe 4.0 speed, based on what I know. They come close, but not close enough.
As there's not PCIe 3.8 standard... Well, they simply won't pass certification and can thus, not be sold as PCIe 4.0 compatible.
 
PCI-e 4 need updated hardware which cannot be obtained by mere software update. Or you can really download updated PCI-e like RAM.

Yeah, it requires a CPU if you did not notice...

PCI-e 4.0 needs new wiring, which cannot be obtained simply by updating firmware.

Explain the firmware then. It's our and generally works.

It doesn't need new wiring. It's best to cert the wiring for the new standard though, or you may have... intermittent issues. With an SSD could be really worrisome.

PCI-e 4.0 needs new wiring, which cannot be obtained simply by updating firmware.

Explain the firmware then. It's our and generally works.

It doesn't need new wiring. It's best to cert the wiring for the new standard though, or you may have... intermittent issues. With an SSD could be really worrisome.

They come close, but not close enough.

They probably are transmitting at full speed, but dropping some data. PCIe error checking will fight this, but can only do so much.

Crappy risers in mining did similar things.
 
Hmm, i was like 570x is a dealbraker in price, this kinda puts it back in play for me to get AMD.
i would be satisfied with 1 lane pcie-4.
Given the massive overclocking potential of the 3000 series I see your point
 
Given the massive overclocking potential of the 3000 series I see your point
I felt the same in the beginning, then i kinda reckognized the workhorse it is.
 
PCI-e 4.0 needs new wiring, which cannot be obtained simply by updating firmware.
The GPU's support new standard, then why we need new cable for new Display Port or HDMI standard?? Cause new standard has new requirement that old cable dont support. Like this new PCI-e need new wiring in PCB, old wiring were designed PCI-e 3.0 in mind not PCI-e 4.

It has nothing to due with wiring. It has all to do with signal integrity. I don't see why AMD won't just let the motherboard vendors work it out on their own? Just keep it enabled as an option but only officially support it on X570 and thats that. It costs AMD nothing.
 
It has nothing to due with wiring. It has all to do with signal integrity. I don't see why AMD won't just let the motherboard vendors work it out on their own? Just keep it enabled as an option but only officially support it on X570 and thats that. It costs AMD nothing.

Because it can cause serious problems. Users will blame AMD. Why is this so hard to understand?
 
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