Motherboard of choice for 6 or more GPU's

[lbr]

SIX is the max number for windows 7.

not true.

[dalegod]

I have 6 cards per rig, 3 of them on powered risers... two rigs... 3 Seasonic 1250 Watt gold power supplies.  Each power supply powers 4 cards.

I have the Gigabyte 990FXA-UD5 and the MSI 990FXA-GD80 and they both can handle 6 GPU's I believe (still waiting on 1x risers to arrive).  It looked like they had been out for awhile so I didnt know if there was anything better on the market that most people were using or not.

Hey I have the GA-990FXA-UD5 and do you have to short one of the slots to get the 6th working?

I'm curious what kind of luck you have had getting six cards to run on this mobo.  I have two of these going each with five cards.  Four of the cards are on the 16x PCIe slots and one is on a 1x PCIe slot.  When I built the rigs I couldn't get the second 1x PCIe to work.  Just curious if you had luck maxing out the PCIe's on the GA-990FXA-UD5.

(My friend was surprised I got Gigabyte motherboards to work at all!  They don't always reboot correctly on the first try--could be the cheap SSD or anything else though--I'm no expert!)

[MangoJ]

SIX is the max number for windows 7.

not true.

Yes True.
I personally have multiple 5870s and 5970s.
5970s are dual GPUs.
I have motherboards with 6 PCI slots.
I can install six 5870s.
Or I can install two 5970s and two 5870s.
I cannot install more than three 5970s.
I can not install one 5870 and three 5970s.

I have personally verified that you can not install more than 6 GPUs with windows 7.
I have looked this up online to find that Windows 7 maxes out at 6 GPUs and Linux maxes out at 7 GPUs.

If you disagree, then explain.

[jaywaka2713]

I have looked this up online to find that Windows 7 maxes out at 6 GPUs and Linux maxes out at 7 GPUs.

If you disagree, then explain.

Linux actually doesn't max out at 7 GPUs. It has no theoretical limit on the amount of cards you can load onto it. The largest motherboard out there has 8 slots I think and it supports every one.

[lbr]

I have personally verified that you can not install more than 6 GPUs with windows 7.

The only thing you've personally verified is the fact that you were unable to install more than 6 GPUs with windows 7.

Windows XP 32 bit + 8 GPUs - http://foldingforum.org/viewtopic.php?f=38&t=7902&start=270#p115136
Yeah.. that's two core nvidia cards, but they do count as GPUs, right ; )

I think that there is no hard coded limit or any limitation of GPUs in both Linux and Windows.
However when installing 8+ GPUs there are certain issues with BIOS unable to map all the GPUs.
Can't remember the project name right now, but guys made 10(not sure about the number but above 8 ) nvidia GPU rig, they had to use custom BIOS and custom linux kernel pathes to make it work.

Plus there is known issue with Windows ATI driver, which prevents you from n+ GPUs drivers being properly installed.
Some people claim n=4, some n=5.
For my setup(GA-990FXA-UD3 + 2x6950 + 2x7950) n=5. And in order to use 6GPUs in Windows I needed either to use 12.6 driver downloaded from AMD or 13.1 driver downloaded from techpowerup.

Also that 13.1 from techpowerup driver is different from 13.1 from AMD driver only in registry, so I assume that with some mod it is possible to use any driver version for 6GPU rigs.

So unless s1 explains why it is not possible technically to use 6+ AMD GPUs in Windows I consider it is doable.
"Windows sux"/"I was not able to use more than n GPUs in Windows"/"AMD drivers are crap" are not technical explanations.

[lbr]

So, to sum it all up.

5 GPUs - Win/*nix out of the box
6 GPUs - Win+12.6 / Win+13.1 techpowerup / *nix out of the box(? have not verfied myself)
8 GPUs - Win?? / *nix out of the box??
8+ GPUs - a lot of pain ; ) BIOS mods/ *nix kernel mods

[jaywaka2713]

So, to sum it all up.

5 GPUs - Win/*nix out of the box
6 GPUs - Win+12.6 / Win+13.1 techpowerup / *nix out of the box(? have not verfied myself)
8 GPUs - Win?? / *nix kernel tweaking/driver tweaking??
8+ GPUs - a lot of pain ; ) BIOS mods/ *nix kernel mods

[MangoJ]

I have personally verified that you can not install more than 6 GPUs with windows 7.

The only thing you've personally verified is the fact that you were unable to install more than 6 GPUs with windows 7.

Windows XP 32 bit + 8 GPUs - http://foldingforum.org/viewtopic.php?f=38&t=7902&start=270#p115136
Yeah.. that's two core nvidia cards, but they do count as GPUs, right ; )

I think that there is no hard coded limit or any limitation of GPUs in both Linux and Windows.
However when installing 8+ GPUs there are certain issues with BIOS unable to map all the GPUs.
Can't remember the project name right now, but guys made 10(not sure about the number but above 8 ) nvidia GPU rig, they had to use custom BIOS and custom linux kernel pathes to make it work.

Plus there is known issue with Windows ATI driver, which prevents you from n+ GPUs drivers being properly installed.
Some people claim n=4, some n=5.
For my setup(GA-990FXA-UD3 + 2x6950 + 2x7950) n=5. And in order to use 6GPUs in Windows I needed either to use 12.6 driver downloaded from AMD or 13.1 driver downloaded from techpowerup.

Also that 13.1 from techpowerup driver is different from 13.1 from AMD driver only in registry, so I assume that with some mod it is possible to use any driver version for 6GPU rigs.

So unless s1 explains why it is not possible technically to use 6+ AMD GPUs in Windows I consider it is doable.
"Windows sux"/"I was not able to use more than n GPUs in Windows"/"AMD drivers are crap" are not technical explanations.

So it sounds like you are saying windows XP can do 8 GPUs.
Had I known that I would have tried XP and skipped windows 7.  But XP wanted dummy plugs on the DVI ports of unused cards.
That was why I went with windows 7.
Also finding PSUs to support 7 GPUs rather than 6 ended up needing 3 PSUs rather than 2 (When you go the economy path)

I am impressed someone else got 8 to work.  Linux?

I read that windows 7 (not XP) is limited to 6 because they never imagined anyone would want more then 6 GPUs.

[jaywaka2713]

because they never imagined anyone would want more then 6 GPUs.

THIS. This is the reason I have gone with Linux and ditched Windows. With Linux, they didn't imagine ANYTHING. With Linux, you can do almost anything. Almost everything is supported, and if you know what your are doing, almost everything works.

With Windows, you can do what they expect people to do.

[lbr]

because they never imagined anyone would want more then 6 GPUs.

THIS. This is the reason I have gone with Linux and ditched Windows. With Linux, they didn't imagine ANYTHING. With Linux, you can do almost anything. Almost everything is supported, and if you know what your are doing, almost everything works.

With Windows, you can do what they expect people to do.

* lbr *facepalmed to death*

[jaywaka2713]

because they never imagined anyone would want more then 6 GPUs.

THIS. This is the reason I have gone with Linux and ditched Windows. With Linux, they didn't imagine ANYTHING. With Linux, you can do almost anything. Almost everything is supported, and if you know what your are doing, almost everything works.

With Windows, you can do what they expect people to do.

* lbr *facepalmed to death*

Explain why on a Linux server you can actually use it to pull GPU resources from multiple rigs under one application while Windows couldn't of even dream of doing such a thing.

[MangoJ]

because they never imagined anyone would want more then 6 GPUs.

THIS. This is the reason I have gone with Linux and ditched Windows. With Linux, they didn't imagine ANYTHING. With Linux, you can do almost anything. Almost everything is supported, and if you know what your are doing, almost everything works.

With Windows, you can do what they expect people to do.

* lbr *facepalmed to death*

Explain why on a Linux server you can actually use it to pull GPU resources from multiple rigs under one application while Windows couldn't of even dream of doing such a thing.

Because Windows is and always has been the worst, poorly made operating system.  Designed for resale of updates, with intentional problems left in to help promote the next version for sale.

[ssateneth]

SIX is the max number for windows 7.

not true.

Yes True.
I personally have multiple 5870s and 5970s.
5970s are dual GPUs.
I have motherboards with 6 PCI slots.
I can install six 5870s.
Or I can install two 5970s and two 5870s.
I cannot install more than three 5970s.
I can not install one 5870 and three 5970s.

I have personally verified that you can not install more than 6 GPUs with windows 7.
I have looked this up online to find that Windows 7 maxes out at 6 GPUs and Linux maxes out at 7 GPUs.

If you disagree, then explain.

I disagree with you. This picture is all the explaining that is needed. Yes this is windows 7.

[MangoJ]

Very impressive.
Modded Bios?
Modded system?
Windows 7 out of the box with The newest SDK and Catalyst drivers, 5800 and 5900 series ATI cards cannot do that.
Will you tell your secret?

[Beaflag VonRathburg]

Very impressive.
Modded Bios?
Modded system?
Windows 7 out of the box with The newest SDK and Catalyst drivers, 5800 and 5900 series ATI cards cannot do that.
Will you tell your secret?

Read the thread. All of the information is already posted.

[MangoJ]

Very impressive.
Modded Bios?
Modded system?
Windows 7 out of the box with The newest SDK and Catalyst drivers, 5800 and 5900 series ATI cards cannot do that.
Will you tell your secret?

Read the thread. All of the information is already posted.

How to do it is not posted.  Just vague comments like "modded kernel" etc.
No actual information, guide, tutorial, or links to what exactly is modded and how.
Perhaps that is too much to ask on a threat about Motherboards and not software setup.
Oh well.
I'm off this thread.

[ssateneth]

Windows 7 out of the box with The newest SDK and Catalyst drivers, 5800 and 5900 series ATI cards cannot do that.

Thats your problem.

Use 11.12 drivers and 2.5 SDK. Nothing is "modded". Just use software that is known to work.

[Beaflag VonRathburg]

Very impressive.
Modded Bios?
Modded system?
Windows 7 out of the box with The newest SDK and Catalyst drivers, 5800 and 5900 series ATI cards cannot do that.
Will you tell your secret?

Read the thread. All of the information is already posted.

How to do it is not posted.  Just vague comments like "modded kernel" etc.
No actual information, guide, tutorial, or links to what exactly is modded and how.
Perhaps that is too much to ask on a threat about Motherboards and not software setup.
Oh well.
I'm off this thread.

Yes, it is. Read:
https://bitcointalk.org/index.php?topic=186877.msg2222736#msg2222736
and
https://bitcointalk.org/index.php?topic=186877.msg2322687#msg2322687

Or, like I said... Read the thread.

This will also help as well:
https://bitcointalk.org/index.php?action=search;advanced

[wojgp]

Hi
I have a MSI Z77-GD65 mobo with 5 x HD7870 XT Tahiti.  1 of these cards show error 43 (although all 5 are detected) and 4 are listed correctly in device manager. Is there any solution to use 5 or even 6 cards on this mobo ? I tried powered risers etc. , but only 13.1 drivers.
Do You think there is a reason to try with 12.6 or different ? Should I use win8 instead ?
Please help.

[lbr]

why do people still spread this powered riser FUD? I have NEVER used a powered riser, and I have never had problems. All my rigs have 6 cards (8 gpu for 5k series, or 6 7970) and use 16x and 1x slots all with 1x > 1x risers. Been mining since july 2011.

Just because you did not have issues - does not mean powered risers are FUD ; )
Yesterday my friend burnt couple of non-powered 16x-1x risers and before that mb and the same conf with powered risers have no issues.

Also using powered risers makes perfect sense technically speaking unless you have proof that all the GPUs are using no more than 10W from PCI-E slot and that all the motherboards are capable providing 10W on each PCI-E slot(or any other W combination which won't burn mb power regulator).

p.s.
I'm also running non-powered risers on all my rigs with no issues.

edit 2013/07/28: After running ~2months 24/7 my rig burned ; ) PSU ATX motherboard connector to be exact.

Gigabyte GA-990FXA-UD3 rev. 3.0, 2x6950 + 4x7950, Enermax Revolution 85+ 1250W, all card via x16_x1 non-powered risers.

PSU ATX motherboard connector burned after running 24/7 for ~2months.