Friday, December 18th 2020
ASUS Enables Resizable BAR Support on First-Generation AMD Ryzen CPUs
When AMD introduced its Smart Access Memory (SAM) technology, it was used as one of the key advertising points for its 5000 series of Ryzen processors based on Zen 3 architecture. At the time of launch, it was believed that only the latest generation of Ryzen processors can support it and only AMD GPUs can see a benefit in performance. However, later on, many of the motherboard makers have been playing with BIOS updates and have found a way to enable resizable BAR, the technology used for SAM, on non-AMD platforms. Today, thanks to the Reddit user Merich98 we have found out that ASUS has enabled resizable BAR support via BIOS update.
The user has used BIOS version 2409, released just a few days ago, on ASUS B450-PLUS motherboard. The feat is no extraordinary because it works on a B450 motherboard, it has been supported for a long time, but rather the feat is impressive because it works with the first generation AMD Ryzen 7 1700 processor. This contradicts the theory that SAM only needs 5000 series AMD Ryzen processors to run. However, the gains were not that great. On average, the average frame rate number has increased by a small +0.839%. This could be attributed to some margin of error, so it seems like SAM is not giving much performance uplift in this case.
Source:
WCCFTech
The user has used BIOS version 2409, released just a few days ago, on ASUS B450-PLUS motherboard. The feat is no extraordinary because it works on a B450 motherboard, it has been supported for a long time, but rather the feat is impressive because it works with the first generation AMD Ryzen 7 1700 processor. This contradicts the theory that SAM only needs 5000 series AMD Ryzen processors to run. However, the gains were not that great. On average, the average frame rate number has increased by a small +0.839%. This could be attributed to some margin of error, so it seems like SAM is not giving much performance uplift in this case.
34 Comments on ASUS Enables Resizable BAR Support on First-Generation AMD Ryzen CPUs
Now MSI, do the same for both the non-AGESA-supporting 3000 series Ryzens and one that does support them :D plzkthxbye
(actually interesting ASRock didn't do it first)
Why did he not check with a title that has significant gains from SAM.
even now i have duplicates for a bunch of BIOS settings - and they often dont even match up (i have two "AMD overclocking" sections and they dont sync settings on my B450 and x570 asus boards)
Also doesnt the GPU need to support it in the drivers for it to actually enable? So he'd need a 6800 or 6900 card?
Another aspect with mGPU and DX12 could it be leveraged with this to have each GPU to stripe data to VRAM across them? I feel like mGPU could be better with data striping VRAM and GPU processing potentially think lucid hydra type approach. I really feel they were onto something in concept, but it never quite materialized for consumers. To me I see a huge potential on data stripe parity VRAM across multiple GPU's with DX12 because it can pool the VRAM resources from what I recall. I don't know if it can do data parity VRAM allocation across them though it would be enormous with SAM and the increased aperture BAR size across multiple PCIE slots and GPU's!!? Something else as well the way Radeon Boost functions it plays right into SAM's strengths. This really could impact the landscape of mGPU with VRAM allocation data parity across numerous cards and PCIE buses like RAID-5 for the GPU's BAR size basically and with dynamic variable resolution in the case of Radeon Boost that helps make heavier usage out of SAM.
In theory with the data parity across 4 GPU's with interlacing and MFAA you could render it all at the same speed as a single 1 frame, but actually be rendering 4 separate frames across 4 different GPU's and utilizing the resources striped across each. The interlacing wouldn't be as ideal on resolution clarity, but the temporal rendering from MFAA could possibly lessen the impact of it plus spreading it across 4 frames would reduce some of the shimmer negatives of interlacing at the same refresh rates and MFAA itself reduces shimmer as well so a win/win you end up with 4 GPU's doing the work and at 1/4 the resource overhead of MSAA with progressive scan by using interlacing and MFAA. If I'm not mistaken you can define that right in the INF file itself or in the windows registry. I think the BIOS firmware support is the real hurdle it's getting MB makers to adopt and enable it to be used in the first place. Until the MB makers enable support for it the GPU makers certainly can't enable support. They are, but do you blame them for following in their footsteps with the examples they set and used weren't a positive thing for AMD nor consumers that suffered in the same manner!!? What goes around comes around correct? I'm not saying it's great for consumers, but I at least see AMD's perspective they kind of took advantage of a situation a bit in the same manner the others have in the past. It's no more a problem that AMD did it than if it had been Intel or Nvidia and looking at objectively it's hard to fault them doing in turn to them to their competitors what's been done to them in these situations leveraging a perk they were able to discover to exploit and manipulate so to speak. It's how the corporate world operates unfortunately for us consumers. Bottom line though AMD kick started the push for SAM support to the benefit of every much like they did with Mantle and it's influence on DX12 and other things along the way.
Your just not getting support for older generation(s). Simple as that. You will get support on the 5x00 generation(s).
If you have this option in the 3x0 series it does'nt mean it offers anything beneficial. It was said that it works best with a 6800 class GPU that contains 16GB of ram. Not anything below.
Might work if I had a SATA drive. Sadly, my 6800 will be SAM-less for now.
I believe we'll find out that the smaller the VRAM size on a card, the less of a difference this makes - so that performance gain seen on 6x00 cards will be smaller on anything else to the point of not mattering.