11-14-2013, 12:20 AM
Im wondering if anyone is aware of whether there is a limit to the number of GPUs that can be installed in a single system? Specifically AMD cards in a Linux system.
I saw a reference here to indicate that 10+ cards in a single system is not possible, but I have not been able to find any information anywhere on why this is the case (e.g. is the limitation enforced by the driver or something else?) The Catalyst driver information I have been able to find is frustratingly unhelpful in listing a maximum number of supported GPUs. The oclhashcat-plus page says up to 128 GPUs are supported, so I'm assuming that's not the limitation.
We currently have a 8 GPU system with the 8 GPUs seated in an external frame with its own power (2 x 1200W power supplies handling 4 cards each) and cooling and connected to the MB with 2 x 4 way PCIe splitters. There are 2 empty PCIe slots on the machine and I was thinking about getting two more splitters and 8 more cards to make a total of 16. We have a power meter on the MBs power supply which shows that even under full load the GPUs are not pulling much power through the MB, so the additional load from 8 more GPUs should be able to be handled through installing their own dedicated supplies. As long as I can find a way to physically arrange things so they all fit together, I cant think of any hardware related reasons why this couldn't work unless there's some limit in the motherboard that I'm not aware of.
Is anyone aware of any concrete reason why this would not work? Something that I'm not thinking of? The obvious way for me to find out is just to test it, but I wanted to see if anyone here was aware of any potential problems before I do so.
Thanks
I saw a reference here to indicate that 10+ cards in a single system is not possible, but I have not been able to find any information anywhere on why this is the case (e.g. is the limitation enforced by the driver or something else?) The Catalyst driver information I have been able to find is frustratingly unhelpful in listing a maximum number of supported GPUs. The oclhashcat-plus page says up to 128 GPUs are supported, so I'm assuming that's not the limitation.
We currently have a 8 GPU system with the 8 GPUs seated in an external frame with its own power (2 x 1200W power supplies handling 4 cards each) and cooling and connected to the MB with 2 x 4 way PCIe splitters. There are 2 empty PCIe slots on the machine and I was thinking about getting two more splitters and 8 more cards to make a total of 16. We have a power meter on the MBs power supply which shows that even under full load the GPUs are not pulling much power through the MB, so the additional load from 8 more GPUs should be able to be handled through installing their own dedicated supplies. As long as I can find a way to physically arrange things so they all fit together, I cant think of any hardware related reasons why this couldn't work unless there's some limit in the motherboard that I'm not aware of.
Is anyone aware of any concrete reason why this would not work? Something that I'm not thinking of? The obvious way for me to find out is just to test it, but I wanted to see if anyone here was aware of any potential problems before I do so.
Thanks
