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Posted by ET3D - Fri 13 Nov 2020 13:22
That's good to see. We're used to seeing NVIDIA show custom solutions and AMD go for open standards, but here it seems like AMD locked this solution to Ryzen 5000 for no good reason but marketing. If NVIDIA presents something that works on all CPUs, perhaps we'll see AMD expand the use of SAM to at least Ryzen 3000.
Posted by Nifl - Fri 13 Nov 2020 13:37
So Nvidia is trying to say they have been already working on it and have not released or announced it yet even though their R&D budget is way bigger? I smell BS.
Posted by AGTDenton - Fri 13 Nov 2020 13:48
Nifl
I smell BS.
AKA fear of finally losing a sizable market share.


Even if nVidia reacts, they're still going to lose bang for buck
One thing is good, however, competition, competition, competition! In the style of Ballmer
Posted by QuorTek - Fri 13 Nov 2020 14:00
So if AMD get the same boost on workstations and servers and super computers, where money is earned… then it can be grim for both NVIDIA and Intel both in one, however Intel is working on GFX now as well so both the big x86 companies has GFX.
Posted by Spud1 - Fri 13 Nov 2020 14:27
AGTDenton
One thing is good, however, competition, competition, competition!

Exactly. That's the positive here - as one of the companies adds something different, the others react with an equivalent and continues onwards improving the products for all of us no matter which manufacturer you buy :)

SAM itself isn't massively interesting given how meager the gains seem to be in the real world, but every frame counts!
Posted by mattburnzy - Fri 13 Nov 2020 14:32
ET3D
That's good to see. We're used to seeing NVIDIA show custom solutions and AMD go for open standards, but here it seems like AMD locked this solution to Ryzen 5000 for no good reason but marketing. If NVIDIA presents something that works on all CPUs, perhaps we'll see AMD expand the use of SAM to at least Ryzen 3000.
Has this been confirmed that its just marketing?
Posted by LSG501 - Fri 13 Nov 2020 14:38
Does seem a little strange that they haven't already implemented something that is in the pcie spec if it gave such benefits to performance….5-10% performance gains isn't exactly small when it's essentially just code that's being changed, but then I suppose that's what happens when you sit on your laurels due to no real competition….
Posted by DanceswithUnix - Fri 13 Nov 2020 15:06
Nifl
So Nvidia is trying to say they have been already working on it and have not released or announced it yet even though their R&D budget is way bigger? I smell BS.

They are bound to have been working on it, this has been a part of the PCIe specification for years. So at some point Intel CPUs are bound to support it, and Nvidia cards.

AIUI you need both CPU support as that is the PCIe root bridge and BIOS support to set up the cards. That's before the drivers can start supporting it, and there is probably some OS support needed as well.

Looking on my machine here on Linux using “lspci -v” as part of the output I can see:

0c:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Vega 10 XL/XT [Radeon RX Vega 56/64] (rev c3) (prog-if 00 [VGA controller])
        Subsystem: ASUSTeK Computer Inc. Device 0555
        Flags: bus master, fast devsel, latency 0, IRQ 85
        Memory at e0000000 (64-bit, prefetchable) [size=256M]
        Memory at f0000000 (64-bit, prefetchable) [size=2M]
        I/O ports at d000 [size=256]
        Memory at fcc00000 (32-bit, non-prefetchable) [size=512K]
        Expansion ROM at 000c0000 [disabled] [size=128K]
        Capabilities: [48] Vendor Specific Information: Len=08 <?>
        Capabilities: [50] Power Management version 3
        Capabilities: [64] Express Legacy Endpoint, MSI 00
        Capabilities: [a0] MSI: Enable+ Count=1/1 Maskable- 64bit+
        Capabilities: [100] Vendor Specific Information: ID=0001 Rev=1 Len=010 <?>
        Capabilities: [150] Advanced Error Reporting
        Capabilities: [200] Resizable BAR <?>
        Capabilities: [270] Secondary PCI Express
        Capabilities: [2a0] Access Control Services
        Capabilities: [2b0] Address Translation Service (ATS)
        Capabilities: [2c0] Page Request Interface (PRI)
        Capabilities: [2d0] Process Address Space ID (PASID)
        Capabilities: [320] Latency Tolerance Reporting
        Kernel driver in use: amdgpu
        Kernel modules: amdgpu

Note in the middle of the “Capabilities” there lurks a resizable BAR" yet only has a mapped memory region of 256M so doesn't appear to be in use. That's on a Vega 56, so not exactly new, but on an X470 motherboard. Connecting to my server which has a B550 chipset which should support it, the GPU in there is an old R7 360 I had kicking around and that doesn't appear to have a resizable BAR so I can't see if support should work there.

With the Zen 3 and RDNA 2 launches so close AMD have a lot of control over the whole ecosystem, so it seems a good opportunity to get this stuff out there and properly working. Hopefully now AMD has made some noise on this, support will spread.
Posted by Tabbykatze - Fri 13 Nov 2020 16:06
ET3D
That's good to see. We're used to seeing NVIDIA show custom solutions and AMD go for open standards, but here it seems like AMD locked this solution to Ryzen 5000 for no good reason but marketing. If NVIDIA presents something that works on all CPUs, perhaps we'll see AMD expand the use of SAM to at least Ryzen 3000.

They didn't “lock” it down for no good reason, the main reason they were able to do it is that they have both a CPU and GPU division that they can work on internally for it. The actual next step for this is to be CXL which is a vendor ambiguous technology in PCIe 5.0 and above.

AMD would have to tip off both Nvidia and Intel what they are doing and with their financial horsepower would overcome what AMD is trying to be a forward player in the market.

“no good reason” is disingenuous to why they did it at best, it doesn't seem like it's just a microcode update and boom the CPU can now address all of GPU memory instead of the 256MB BAR of PCIe, it requires a little bit more. As AMD has both CPU and GPU, worked a ton on CCIX (competitor to CXL which lost), they were in a prime opportunity to perform acceleration in this area.
Posted by Iota - Fri 13 Nov 2020 17:27
LSG501
Does seem a little strange that they haven't already implemented something that is in the pcie spec if it gave such benefits to performance….5-10% performance gains isn't exactly small when it's essentially just code that's being changed, but then I suppose that's what happens when you sit on your laurels due to no real competition….

I'd probably think there is something stopping them from doing so, otherwise they would have done this already. Perhaps Intel doesn't play nicely, or it's unstable etc etc.
Posted by Sumanji - Fri 13 Nov 2020 18:17
Hoping this forces AMD's hand into enabling SAM on older chipsets and CPU's… actually mildly annoyed at AMD if SAM was an attempt to artificially wall off a needle-moving tech to their newer kit…
Posted by LSG501 - Fri 13 Nov 2020 20:08
Iota
I'd probably think there is something stopping them from doing so, otherwise they would have done this already. Perhaps Intel doesn't play nicely, or it's unstable etc etc.

Could be compatibility issues but, and you can call me cynical here, they've just had no real competition and sat on it for just this occasion now they've got competition. They'll get it out quick smart but notice how the news has been timed to make people question if AMD is the best choice again… admittedly neither's a good choice at the moment because there's basically no stock lol
Posted by lumireleon - Sat 14 Nov 2020 06:13
QUESTION: can the AMD cpu use the GDDR6 as RAM for other compute tasks instead of gaming??
Posted by Tabbykatze - Sat 14 Nov 2020 20:25
lumireleon
QUESTION: can the AMD cpu use the GDDR6 as RAM for other compute tasks instead of gaming??

Could they not before?

What do you mean by your question?
Posted by Corky34 - Sun 15 Nov 2020 08:29
DanceswithUnix
Note in the middle of the “Capabilities” there lurks a resizable BAR" yet only has a mapped memory region of 256M so doesn't appear to be in use. That's on a Vega 56, so not exactly new, but on an X470 motherboard. Connecting to my server which has a B550 chipset which should support it, the GPU in there is an old R7 360 I had kicking around and that doesn't appear to have a resizable BAR so I can't see if support should work there.
It also says it couldn't completely decode that register, i guess because AMD hasn't actually told anyone.
Posted by ET3D - Mon 16 Nov 2020 07:45
mattburnzy
Has this been confirmed that its just marketing?

(Sorry for the late reply, haven't followed the thread.)

For one thing, I have no reason to disbelief NVIDIA that it's part of a standard. Or that it's working on Linux with pretty much everything.

For another, Ryzen 5000 uses the same I/O die as Ryzen 3000, so it makes no sense that something that's purely I/O-related will work only on Ryzen 5000.

Though I guess that the only real confirmation would be when AMD expands support to more platforms, which I expect to happen when NVIDIA releases its solution.
Posted by 3dcandy - Mon 16 Nov 2020 08:04
ET3D
(Sorry for the late reply, haven't followed the thread.)

For one thing, I have no reason to disbelief NVIDIA that it's part of a standard. Or that it's working on Linux with pretty much everything.

For another, Ryzen 5000 uses the same I/O die as Ryzen 3000, so it makes no sense that something that's purely I/O-related will work only on Ryzen 5000.

Though I guess that the only real confirmation would be when AMD expands support to more platforms, which I expect to happen when NVIDIA releases its solution.

PCI Gen4 might be why it's currently Ryzen 5000 and 500 series chipset
Posted by kalniel - Mon 16 Nov 2020 08:23
3dcandy
PCI Gen4 might be why it's currently Ryzen 5000 and 500 series chipset

I thought Nvidia claimed it could work on gen 3 as well.
Posted by Tabbykatze - Mon 16 Nov 2020 08:45
ET3D
(Sorry for the late reply, haven't followed the thread.)

For one thing, I have no reason to disbelief NVIDIA that it's part of a standard. Or that it's working on Linux with pretty much everything.

For another, Ryzen 5000 uses the same I/O die as Ryzen 3000, so it makes no sense that something that's purely I/O-related will work only on Ryzen 5000.

Though I guess that the only real confirmation would be when AMD expands support to more platforms, which I expect to happen when NVIDIA releases its solution.

As far as I understand it, Zen 3 was drop in compatible with the Zen 2 IO die but the Zen 3 IO die is more refined/modified. That's why the memory timings and infinity fabric clock are higher/different in their capable compatibilities.

kalniel
I thought Nvidia claimed it could work on gen 3 as well.

They have said so, they're apparently going to enable on Turing as well.
Posted by 3dcandy - Mon 16 Nov 2020 09:10
kalniel
I thought Nvidia claimed it could work on gen 3 as well.

I did say currently….
Posted by MajorZod - Mon 16 Nov 2020 09:35
Nifl
I smell BS.

Probably worth pointing out that this tech has been in their CUDA workflow for some time. Migrating it to their gaming range has probably been on the cards but as we know NVIDIA like to drip feed new technology into new ranges to give them more unique selling points.
Posted by towell - Mon 16 Nov 2020 11:14
If it truly is a software limitation, and Nvidia truly plans to make it happen on their chips, it's gonna be up to AMD to play ball with Nvidia (or at least up to Nvidia to pony up enough £££ to persuade AMD to enable it). Would hate to see this be only possible on AMD+Radeon or Intel+Nvidia systems…
Posted by DanceswithUnix - Mon 16 Nov 2020 11:53
towell
If it truly is a software limitation, and Nvidia truly plans to make it happen on their chips, it's gonna be up to AMD to play ball with Nvidia (or at least up to Nvidia to pony up enough £££ to persuade AMD to enable it). Would hate to see this be only possible on AMD+Radeon or Intel+Nvidia systems…

That wouldn't make sense. If someone already has an Nvidia card, are AMD going to drive them into using an Intel CPU on their next upgrade or try and suck them into the AM4 eco system?

From the Nvidia side, they would happily work with AMD if it is a poke in the eye for Intel.