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Anyone try to run 4 x R9 295x2's

M

meankeys

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Jul 4, 2014
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Hi all

Anyone try to run 4 x R9 295x2's

I have a RVE 5960X 16 GB corsair Dom Plat

The board will not post. I get a boot loop with three cards. The last Qcode = 95 resources.
Any suggestions would be helpful.
Thanks

http://hwbot.org/user/meankeys/
 
If I'm not wrong you can only use 2 of those in crossfire since they are considered 2 cards each already crossfired.
So techincally you're already hitting the 4 card cap.

If I'm wrong someone correct me, but I think this is your problem.
 
Xorium said:
If I'm not wrong you can only use 2 of those in crossfire since they are considered 2 cards each already crossfired.
So techincally you're already hitting the 4 card cap.

If I'm wrong someone correct me, but I think this is your problem.
Click to expand...

Nope I also agree that this is the problem.
 
I think the problem may actually be a PSU that can't handle four of those cards.
A system should post with more than 4 GPU's, you just can't crossfire. 4x a 295X2 however would need two PSU's in almost all cases, something he probably doesn't have.
 
possible, because TWO x 295x2 is eating a lot of power and read somewhere even one PSU 1500+ cant really handle it at max load. so it should be 2x 1600 PSU or something similar for 4 of these. another thing they will not work in crossfire mode, 4 way crossfire is max (and you trying 8 way crossfire)
 
Mathragh said:
I think the problem may actually be a PSU that can't handle four of those cards.
A system should post with more than 4 GPU's, you just can't crossfire. 4x a 295X2 however would need two PSU's in almost all cases, something he probably doesn't have.
Click to expand...

This is the only problem I can think of. Board will not post due to PSU failing to supply power to all the GPU's. Yes of course in theory you can install 4x dual gpu's but you can only enable 4xgpu. in the case of 295x2, only 2 pcs. Only because AMD and NVIDIA only support up to quad SLI, quad crossfire
 
I was under the impression that, while you couldn't use them in games, you could use all 8 for compute.

But yeah, 4x295x2 isn't going to be powered by one PSU. You'll need two massive PSUs. The last 2 cards by themselves can draw almost 1300w.
They are also either going to need to be on separate breakers or you'll need a separate line run though your house for the wattage. I've seen house circuits cut well before the PSU.

If you want to know which PSU to choose I would go for the LEPA1600. It's already powerful, and a guy on another forum ran a similar setup and drew almost 2000w from it.
 
There's not a single PSU that I know of that will power four R9 290x2. You will need two PSUs and depending on how many amps your breaker is supplying to your wall outlet you may need to plug one of the PSUs into a wall outlet that is on a different breaker.

Edit: I don't know anything about compute but as others have said you can only use 4 GPUs for gaming so if gaming is your intent then don't waste the money. :)
 
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It isn't a PSU issue. If the PSU was overloaded the OCP protection would be kicking in and the machine would be shutting down. It wouldn't be causing POST issues. And while the cards are going to require an insane amount of power under load, when booting they are only going to need a fraction of that.

I'm guessing the more likely cause is the board's BIOS just can't address more than 4 GPUs. When it tries to allocate the resources for the GPUs it freaks out when it sees more than 4 and reboots.
 
newtekie1 said:
It isn't a PSU issue. If the PSU was overloaded the OCP protection would be kicking in and the machine would be shutting down. It wouldn't be causing POST issues. And while the cards are going to require an insane amount of power under load, when booting they are only going to need a fraction of that.

I'm guessing the more likely cause is the board's BIOS just can't address more than 4 GPUs. When it tries to allocate the resources for the GPUs it freaks out when it sees more than 4 and reboots.
Click to expand...

Guy's thanks for the input. It.s not a power problem. I have a 1200W and a 1000W psu to drive the cards. It is possible to run 6 or more cards in win 7 with a modded driver. win 8.1 I think can do it out of the box. I am leaning t words newtekie1 as to my boot problem. I have run 2 r9 295x2's and 2 7950 in this rig no problems. and I have benched two of these r9 295x2's with some decent results.

http://hwbot.org/user/meankeys/

I am prepping my RIVBE for the SS and will see if I can boot 3 r9295x2' on that board. I will post back tonight after I do so testing.

Thanks again for the help
 
It's possible to run more than two, just not in CrossFire.
 
I'd love to see what 8 GPUs (of either brand) in tandem would do. Yeah, there's diminishing returns and all that power and noise, but it would make for a great hardcore enthusiast experiment. :cool:
 
For a few weeks, i had four (4) EVGA gtx 460 2Win folding for TPU, but i never was able to put them all together in one rig. The same problem always arose as soon as i tried to load both gpu cores on any of the cards (except for the fourth one): temps would quickly (i could not even complete a few frames to get some ppd high scores!) rise to over 90c, in which case i would shutdown the client to protect the card. And even without loading them, just being so close together broke four out of the six fans of the two middle cards !

Bottom line: it DOES look cool to have 8 gpus in one rig, but you're gonna need a pretty thick wallet if you want to manage them (advanced watercooling is almost mandatory) .
 
qubit said:
I'd love to see what 8 GPUs (of either brand) in tandem would do. Yeah, there's diminishing returns and all that power and noise, but it would make for a great hardcore enthusiast experiment. :cool:
Click to expand...

Well I got the RIVBE to post with three r9 295x2's but 4 will loop and stop on qcode 94 (PCI Bus Enumeration) still testing.
Going to try a few more things.

4x295x2-RIVBE-1.png
4x295x2-RIVBE-2.png
 
Did you ever get this to work? Maybe you need a sever motherboard.
 
any 3kw PSU should run these cards easily... oh wait....
 
Think of the glaciers.....
 
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