urisavor

Enabling CAL for 2 X HD5970 without crossfire / linux 32bit

Discussion created by urisavor on Aug 3, 2010
Latest reply on Aug 3, 2010 by nou

Hi! I am trying to run a computation-intensive app on 4 GPUs on two HD5970 cards - using CAL.

In default configuration, CAL reports only one device, and indeed allows only one device to be set up.

When crossfire is enabled, I can run two devices, but performance is degraded (instead of getting double the speed, I get about half the speed).

As the threads are independent, I don't need crossfire - I just need to run on all four GPUs - as many threads as possible concurrently.

I was not able to configure the system so tha CAL reports 4 devices, and no crossfire.

System details:

O/S: Ubuntu 10.4, kernel 2.6.32-21-generic

Mobo: Asus 6PT

Thanks,

Uri

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