CPU Instruction Set, Affect GPU Compatibility?

[Kandern97]

So, I'm trying to do a Scrapyard Wars style build.

 

I've found some good Dell Optiplex systems on Craigslist that use 2nd Gen Sandy Bridge CPUs (7010 DT model)

 

I called the guy up, and he said a funny thing that I'm trying to confirm, that "modern" GPUs aren't compatible with Sandy Bridge, due to an incompatible instruction set.

 

I've never heard of anything like this before, and can't seem to find anything about it online. Is it true that different instruction sets of different CPU generations affect GPU compatibility? Or was it more likely that my guy had a problem with his PCI-e or PSU or something else?

 

For reference, he mentioned that he tested a lower power card in the system just fine, using a real PSU (not Dell's proprietary one)

 

Sorry if this has already been mentioned somewhere else; I'm a little over my head on this one.

Edited June 21, 2019 by Kandern97
Model of Optiplex

[Electronics Wizardy]

Modern gpus should work on sandy bridge just fine. I have ran my rx vega 56 on a sandy bridge system with no issues. There may be a few weird combos that don't work, but no major errors.

[RobFRaschke]

I call BS, but let's actually break it down and think critically just to make sure. The Instruction sets and extensions utilized on Sandy Bridge are:

Instruciton Sets:

MMX, AES-NI, CLMUL

Extensions:

x86-64, Intel 64, SSE, SSE2, SSE3, SSSE3, SSE4, SSE4.1, SSE4.2, AVX, TXT, VT-x, VT-d

 

Now let's go all the way up to the latest Cannon Lake architecture(which is idential to the 9th gen Cannon Lake:

Instructions:

x86-64

Extensions:

MMX, AES-NI, CLMUL, FMA3

SSE, SSE2, SSE3, SSSE3, SSE4, SSE4.1, SSE4.2

AVX, AVX2, AVX-512, SHA, TXT, TSX, SGX

VT-x, VT-d

 

Despite the fact that Intel lists them differently, Sandy Bridge doesn't support any instruction sets or extensions that aren't on Cannon Lake. Cannon Lake just adds more, newer extension sets.

 

Sandy Bridge CPUs and their respective motherboards do only Support PCIe 2.0, however unless you want to throw a Vega 64, Radeon VII, or Nvidia XX80 GPU or higher in it, I'm quite confident that won't be an issue.

 

Bios compatability could be an issue, but I would bet that whatever GPU you're trying to get for a junkyard build won't be exactly the latest or greatest, so still, probably not an issue.

[KarathKasun]

36 minutes ago, Kandern97 said:

So, I'm trying to do a Scrapyard Wars style build.

 

I've found some good Dell Optiplex systems on Craigslist that use 2nd Gen Sandy Bridge CPUs (3010 and 7010).

 

I called the guy up, and he said a funny thing that I'm trying to confirm, that "modern" GPUs aren't compatible with Sandy Bridge, due to an incompatible instruction set.

 

I've never heard of anything like this before, and can't seem to find anything about it online. Is it true that different instruction sets of different CPU generations affect GPU compatibility? Or was it more likely that my guy had a problem with his PCI-e or PSU or something else?

 

For reference, he mentioned that he tested a lower power card in the system just fine, using a real PSU (not Dell's proprietary one)

 

Sorry if this has already been mentioned somewhere else; I'm a little over my head on this one.

Lies.

 

Ive got a i7-2600k and every single GPU from the last 10 years works in it.

 

Some high end Z77 boards will let you use PCIe 3.0 with SB chips because they have a PCIe switch in them.  Maximum V Extreme for example lets me run two PCIe 3.0 x8 cards at PCIe 3.0 x8 with my SB i7-2600k.

[Kandern97]

1 hour ago, RobFRaschke said:

I call BS, but let's actually break it down and think critically just to make sure. The Instruction sets and extensions utilized on Sandy Bridge are:

Instruciton Sets:

MMX, AES-NI, CLMUL

Extensions:

x86-64, Intel 64, SSE, SSE2, SSE3, SSSE3, SSE4, SSE4.1, SSE4.2, AVX, TXT, VT-x, VT-d

 

Now let's go all the way up to the latest Cannon Lake architecture(which is idential to the 9th gen Cannon Lake:

Instructions:

x86-64

Extensions:

MMX, AES-NI, CLMUL, FMA3

SSE, SSE2, SSE3, SSSE3, SSE4, SSE4.1, SSE4.2

AVX, AVX2, AVX-512, SHA, TXT, TSX, SGX

VT-x, VT-d

 

Despite the fact that Intel lists them differently, Sandy Bridge doesn't support any instruction sets or extensions that aren't on Cannon Lake. Cannon Lake just adds more, newer extension sets.

 

Sandy Bridge CPUs and their respective motherboards do only Support PCIe 2.0, however unless you want to throw a Vega 64, Radeon VII, or Nvidia XX80 GPU or higher in it, I'm quite confident that won't be an issue.

 

Bios compatability could be an issue, but I would bet that whatever GPU you're trying to get for a junkyard build won't be exactly the latest or greatest, so still, probably not an issue.

Thanks for your reply. That all makes sense.

 

Only thing: I am trying to use an R9 380 for this build. Could I expect to run into bios issues?

[Kandern97]

Ok, I think I figured out why he said that the system wouldn't run his card.

 

Turns out the Dell Optiplex 7010, for some form factors, does not support full 75W on the PCI-e x16 slot! As you can see in the attached picture, the MT (full-size) supports 75W, but the DT (mid-tower) and SFF (small) only will go 50W!

 

So, here's a question about GPU's then. My R9 380 has a TDP of 190W and 2x 6-pin power sockets (75W/ea.). Theoretically, assuming my power consumption correlates close enough to my heat output, I should be fine? Cuz, I'll get (75W * 2) + 50W = 200W?

 

Is that assumption bad, and is there something I don't know about that would make this a bad idea?

 

Link to technical manual for Dell Optiplex 7010 (all models): https://www.dell.com/downloads/global/products/optix/en/optiplex_7010_technical_guidebook.pdf

 

Thanks for all your help!

[KarathKasun]

You could always hotwire the 12v rail on the slot to bypass the current sense circuitry.

 

However, it is also possible that the "50w" limit is just an arbitrary one due to PSU under sizing.  I have seen several systems such as this with RX 480's, which pull 80w from the slot (there were some failures/fires).

[RobFRaschke]

I'd wager he couldn't get a lower end card to work because of that wattage limitation on the socket, but a card with external power connections should work, so long as it doesn't have a junk VRM.