Bitcoin Forum

Hi Folks,

I was wondering if GUIMiner can go beyond 3 GPUs. I have 2 6950s, and 1 5850 plugged in, as soon as I add the 4th 5850 GUIMiner cannot boot up.

Here are my specs incase you're wondering.

MSI 890FXA-G70
Windows 7 64Bit Ultimate
1000W Kingwin Powersupply
All Vidcards have Dummy Plugs
Latest AMD Drivers, so that's 2.4SDK

Can anyone help with this? I've been going at this for over a two days.

People have reported that Windows 7 supports 4 GPUs, other claim to run even more(multi-core at that).

Have you tried Phoenix(with phatk)?

Does it spit out any error message, or just not come up when you launch it?

I also suggest trying the console version of poclbm(guiminer when with gui), it might give you a hint(and us)

I have not tried Pheonix, I have no idea how that works.  I don't know Linux or any coding languages.

Are these in a crossfireX configuration or all standalone?

There are no error messages on this, it simply boots up shows it's icon on the lower right hand corner, then disappears. It automatically shuts down it's process on the task manager also.

Phoenix is a windows miner albeit 32bit i think...if your OS can also run x86 apps, try it.

EDIT: I really suggest running the program in console mode.

Can you make sure that the card is enabled in Windows?

Right-click on the desktop, edit Screen Resolution, and verify that you have "Extend Desktop to this Monitor" enabled (instructions are from memory since I'm on XP atm).

These are all stand alone, Should I cross fire?

Crossfire afaik should in some cases lower mining performance. and you can only CF between series of the same class i.e 6k with 6k and 5k with 5k(and if they are of the same family)

Windows and Catalyst Software will detect all 4 cards, GUIMiner refuses to load when I have 4 cards on. 3 Cards it'll load up just fine.

Worth a shot.  ;D

Hmmm.... :-\

I honestly think that this is just a limitation of the GUIminer. My best opinion would be to switch to a miner that has known support for 4 cards.

Since it seems as if you want to stay away from the CLI, I can script it out for you quite easily. Just name a miner of your choice.

I could whip up an easy batch script to start the miner of your choice if the command prompt is not your cup o' tea.

Well one, guiminer has no problems running multiple cards with multi gpus afaik. And i also suggested a few things, but seems they were ignored(even if they might not be the cause/solution)

Do you have all 4 connected to some sort of display? Or at elast some dummy connection for the 4th card?

I have seen screen shots of 1, 2, 3, 4 different GPUs on GUIMiner, however, if they were individual cards or 2 Multi cards i'm not sure.

As above post says your problem probably is you have the 2 6950's crossfired and no display/dummy plug in the third card

When I launch this on GUIMiner, it crashes the dos prompt that shows up.

They are all stand alone cards. There are dummy plugs on all the VID cards... nothing is crossfired.

Hmm, Try a miner with native x64 support.

If they are 4 different GPU's then it seems as if they are standalones and not crossfired. Which card were you running your display off of when you only had 3 GPUs?

It crashes the DOS prompt or opens and then quickly closes? Are you double-clicking on poclbm or executing it from the prompt?

I had the same problem with 3x 5870 + 1x 6870 and GUIMiner... Everything worked fine with 3 active cards but starting the 4th (it doesnt matter which one) just crashed GUIMiner. I think the problem is caused by mixing 6XXX and 5XXX cards. I ended up using 4x 5870 and everything is working great =)

So as soon as you launch the program it crashes? Or does it only crash when you start mining?

GUIMiner crashes when you start the 4th thread. I also tried phoenix and poclbm console versions but they both crashed when using the 4th card.

If you start that card first, does it crash? Im thinking you may have a bad card. Also, are all the power plugs seated correctly for that card? You may want to double check. If you take out other cards, will starting that thread still make it crash? You need to start eliminating variables to narrow down the problem. I cant imagine it being guiminer, Ive got that same board, running guiminer in XP, and everything works fine with 4x cards. Try swapping cards around in the slots, and see if one of them consistently fails or causes the program to crash. You might even try only 1 card at a time, and mining for a minute or two on each to make sure that each card CAN mine correctly, just to eliminate the "bad card" variable.

I too think it's a bad card, have you mined on it by itself to ensure it's working?

3 out of the 4 cards always work at max. hash rates no matter which cards i choose... i think its an sdk bug when mixing HD 5XXX and 6XXX cards

Maybe its a bad PCI-express slot. Get a can of compressed air and clean out the slots. Could also be a bad motherboard.

Try swapping the cards to different slots. If one card is bad, it will show in a different slot.

Also try rolling back to SDK 2.1 using system restore.

I use SDK 2.1 and I get faster hash rates than other people with similar hardware.

Failing that, you want to try uninstalling all the GPU's in device manager, then click re-scan for new hardware.

First thing's first:

What motherboard are you using. Chipset and model.

Second:

Try using Phoenix Rising, it is a GUI for the popular Phoenix client. http://forum.bitcoin.org/index.php?topic=10264.0

Third:

What kind of power supply, wattage and amperage. Make sure the system isn't firing them all up and crashing because of PSU inefficiencies.

Fourth:

Make sure all cards are active, either using dummy plugs, or plugging them all up to your monitor and extending your desktop to them.

Ok Ive been working on this with the poster last night and this is the issue...


3 gpus, loads up fine
4 gpus, crashes java

Motherboard turns all 4 pcie slots to 8x when 4 cards are equiped. This may be the issue.
 

8x is not an issue. PCIE 1x can push 250Mb/s and mining takes up barely any of that.

Mobo is: msi 890fxa-g70 AMD

The 890FX definitely supports 4 physical GPU's attached.
http://www.amd.com/us/products/desktop/chipsets/8-series-integrated/Pages/amd-890fx-chipset.aspx

Use GPU-Z to check if OpenCL is enabled on each card.
http://www.techpowerup.com/gpuz/

Hmm.. I bet you are using the last Blue PCIe slot because of space issues aren't you?

According to the spec, that last slot on the MB is nonstandard, it was a regular PCI slot MSI decided to change to a 4xPCIE

Maybe MSI's custom solution is fracking with the driver.

"The next change is that of removing one of the older PCI slots and replacing it with a PCI-E slot which can accommodate up to 4x PCI-E lanes.  This slot should not be used for CrossFire though.  The board still features the 4 x PCI-E 16 length slots which will support up to 4 x 8X PCI-E 2.0 lanes in total." http://www.pcper.com/reviews/Motherboards/MSI-890FXA-G70-Motherboard-Review/890FX-Changes-and-MSI-Version

Despite not using crossfire, that may still be causing issues.

Check your manual to make sure that is the right slot though.


If that is the case:
Try getting a PCIE16x Extension cable.
http://www.orbitmicro.com/global/pe-flex16-16-8-3-p-14390.html?ref=base

I am betting you can find one cheaper somewhere.

I have a similar board with space for four 2-slot cards. Mine is the 790FX-GD70 and i have all four slots occupied with Radeons, NOT in crossfire, and all are working in Win7 x32 with SDK 2.1 and Catalyst 11.5.

Did you run Windows Update? I have all the latest updates installed.

I have the MSI 890FXA-GD70 currently running 4 XFX 5850's with GUIMiner, Win 7 x64, Catalyst 11.5 and SDK 2.1, so I know that it can work with four cards in those slots.

I did originally have a problem getting one of the cards running correctly at first though and it turned out to be a power issue.  Even though I had a 850W corsair with a single power rail, I had to mess around with the plugs to get everything working correctly and powered.

What exact Kingwin PSU do you have?  If it has multiple rails, you could very likely be overloading one specific rail and some creative tests might help you figure it out.  For example.  Take the power plugs you have in the card that isn't working and swap it with one that is working.  If the one that wasn't working starts working and vice versa, it's a power issue with those plugs.  Also, if you're using any of those molex to 6 pin adapters, give them all a once over.  I've actually seen it where if the molex power plug is too tight, it'll push the pin out the back of the molex adapter enough that there's no contact.

Even though you have 1000w, a PSU will not put out that max.  Some of the best PSU's I've seen are 90% efficient meaning it should handle 900 watts and yours could be even less efficient.  The 6950's can pull from 160 to 200W each depending on overclock and the 5850's will draw 150-175.  So, worst case, you're looking at 750 watts just in GPU's.  Depending on what else you have on the board, you could be close to the max it's putting out.

Not enough power or the dummy plugs are confusing GUIMiner? :l

I think I can help you but it would be best done via some type of instant messaging.

Can you PM me some way to contact you?

PM me and I can help you over teamviewer or skype or something.

any updates on this.  I have the same problem and I posted a bug report here:

http://forum.bitcoin.org/index.php?topic=3878.msg192377#msg192377

One additional piece of info.  If I boot up with all four cards plugged in, but with the fourth card not hooked up to a monitor, guiminer will open and I can mine with the 3 active cards.

Switching cards/slots/power cables/etc has no affect.

I fixed this problem by using Crossfire.