Bitcoin Forum

Windows only detects 4, is this the maximum? I was unable to find any helpful information on the forums.

The max on windows should be 8 try updating your catalyst drivers.

You'll need to use Catalyst 11.6B or newer drivers to see up to 8 GPU. Due to this, the limit's seems to be in the drivers, not Windows itself.

I can confirm this.

I am running Windows 7 enterprise with 3x 6990 cards, which is 6x GPUs, using the 11.8 preview driver. The rig does some 1600 MHash/s which I currently split between solo and pool.

I am mining with 5 per machine using 11.7 drivers with win7.

That's what I thought. I'm curious about that. Shouldn't it be in the 3ghash/s range?

I'm assuming its a typo 2600 makes a bit more sense then 1600. That's 433 per core.

Anyone have a screen shot to confirm more than 4 can run under Win7 and hash?

I'm at work but I have a rig on win7 32 bit with 5 5850's. It gets around 1950 megahash.

That sounds right on the money, thank you for confirming. Guy with 3x6990's numbers had me questioning this. Now time to order up some risers got 7 pcie's waiting to be tapped :)

Just a heads up. Some motherboards have 6+ pcie slots but don't allow you to use them all. What board do you have? Also I'm pretty sure the limit is 8 gpu's not 8 physical graphics cards so you couldn't run 7 6990's on one mobo as they have dual gpu's.

7 MSI GD70's, just going to run 5 on each, psu limited beyond that. I understand it's 8 gpu cores limited.

It's a good board I own two. Yea after you reach 5-6 cards your reaching the top end of psu's. If you add any more your going to need dual psu's.

I also have 3 X 6990's with clocks set at 900/840(OC switch in default position) I get between 400mh/s - 405mh/s per GPU which is around 2400 mh/s, I would turn the OC switch on and crank the core up but I have cooling problems so I stick with 900/840 settings...