Multiple Video cards locking up

Hey All

I'm building a system for cryptocoin mining, and am having a little problem with getting Windows 8.1 (home, not pro) to run the 3rd card (GPU) My equipment is:

Gigabyte 990 FXA UD3 MOBO
AMD Vishera CPU
2x4 gig Corsair Ram
3x Sapphire r9 280x Video cards
1000w Corsair PSU
Scandisk SSD

All parts are brand new.

Here is the problem... everything boots just fine and runs with 2 of the GPU's installed. I have the latest AMD 13.12 drivers, and the AMD APP SKD installed. When I add the 3rd GPU though, windows will auto detect it as a Radeon 7900 with the caution sign, AND/OR a r9 200 series card, also with the caution sign, most times BOTH. Then it randomly freezes the system. A couple of times I got it to run long enough just by luck I guess, to install the 13.12 drivers on the 3rd GPU, but then in a few minuites the system would freeze again.

2 GPU's run just fine, the problem only shows up when the 3rd card is installed, and it happens on any of the 4 16x slots, or both 1x slots on the MOBO. It doesn't matter if the GPU's are directly on the MOBO, or on 1x16 risers. There are plenty of folks running this set up with up to 6 GPU's, so I know it can be done, but I must be missing something somewhere in the windows set up.

Does anyone have any suggestions?

You don't install drivers for extra cards. They all use the same driver and if it is installed already for others, then good.

Try updating motherboard bios to newest, as a start.

I would also check the motherboard manual to make sure three graphics card used at once is supported, no matter what slots there are or are not:

1. 2 x PCI Express x16 slots, running at x16 (PCIEX16_1, PCIEX16_2) (Note 3)
2. 2 x PCI Express x16 slots, running at x4 (PCIEX4_1, PCIEX4_2)
3. 2 x PCI Express x1 slots (All PCI Express slots conform to the PCI Express 2.0 standard.)
4. 1 x PCI slot

This stands out to me as not good for your situation:

1. Support for 2-Way AMD CrossFireX™ and NVIDIA SLI™ technology (PCIEX16_1, PCIEX16_2)

Notice the bold.

Probably time to return the 3rd card if possible, or if not, EBAY.

MasterChief said:

You don't install drivers for extra cards. They all use the same driver and if it is installed already for others, then good.

Try updating motherboard bios to newest, as a start.

I would also check the motherboard manual to make sure three graphics card used at once is supported, no matter what slots there are or are not:

1. 2 x PCI Express x16 slots, running at x16 (PCIEX16_1, PCIEX16_2) (Note 3)
2. 2 x PCI Express x16 slots, running at x4 (PCIEX4_1, PCIEX4_2)
3. 2 x PCI Express x1 slots (All PCI Express slots conform to the PCI Express 2.0 standard.)
4. 1 x PCI slot

This stands out to me as not good for your situation:

1. Support for 2-Way AMD CrossFireX™ and NVIDIA SLI™ technology (PCIEX16_1, PCIEX16_2)

Notice the bold.

Probably time to return the 3rd card if possible, or if not, EBAY.

Click to expand...

Yeah, I thought of all that... I don't have them crossfired, and the system runs fine on any 2 cards. So I don't think I have a bad card. I tried switching them around thinking it might be a bad card, and always get the same result. Any 2 cards runs fine, the problem only pops up when I add the 3rd card.

I don't really think it's a bios problem, other wise Windows wouldn't see the 3rd card at all? I know the MOBO will support it, there are lot's of folks running the exact same set up and no one has them cross fired.

Windows see's the 3rd card, even with the new drivers, but then locks up and goes to black screen.

Basically, what I'm saying is that you cannot physically have 3 video cards in at the same time and have them work well, with this motherboard. (Most likely - and the reason for the issue.)

Even if you could, they would need to be in 3-way Crossfire for mining to use them all at once, and that for sure is not possible.

MasterChief said:

Basically, what I'm saying is that you cannot physically have 3 video cards in at the same time and have them work well, with this motherboard. (Most likely - and the reason for the issue.)

Even if you could, they would need to be in 3-way Crossfire for mining to use them all at once, and that for sure is not possible.

Click to expand...

No... there is room to have all 3 on the MOBO in 16x slots, just lucky on the slot spacing...but I'd never run them that way, no room for air flow. 2 of them are on powered 1x to 16x risers to space them out. It doesn't matter if all 3 are directly on the board, or on risers. Windows always pukes on the 3rd card.

Room doesn't matter. It's the architecture and design of the board.

Windows doesn't puke on 3rd card. Your motherboard does.

So even if you put Linux, what you are trying to accomplish is never going to happen.

You need something like ASUS Rampage IV Extreme.

"The board features SLI/CrossFire on Demand technology, supporting up to four graphics cards in a four-way SLI or CrossFireX configuration."

Your current board: "Up to 2 VGA cards are supported"

See the difference?

MasterChief said:

Room doesn't matter. It's the architecture and design of the board.

Windows doesn't puke on 3rd card. Your motherboard does.

So even if you put Linux, what you are trying to accomplish is never going to happen.

You need something like ASUS Rampage IV Extreme.

"The board features SLI/CrossFire on Demand technology, supporting up to four graphics cards in a four-way SLI or CrossFireX configuration."

Your current board: "Up to 2 VGA cards are supported"

See the difference?

Click to expand...

Yepper... Thanks for your help!