These days, I have a number of dual GPU setups, both RX 460 and R7 370. I take care to 'match' the GPUs - same brand, same model. The motherboards have x16 slots that are x16, x4 electrically. The first thing I noticed was that the device that BOINC identified as device 1 was a bit faster than device 0. I assumed that device 0 would be in the x16 slot and device 1 would be x4 -- obviously not, so it would seem.
The difference wasn't all that large, particularly with Polaris, so I didn't investigate further. The worst case I recall seeing was with dual R7 370s with both devices running GPU tasks 2x (4 GPU tasks all up). Device 0 was reporting crunch times of around 37 mins and device 1 around 33 mins.
Presumably PCIe x8 should be less of an issue than PCIe x4 and might contribute to a slowdown but perhaps not the variability of any slowdown.
PCIe x8 may be a factor and i
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PCIe x8 may be a factor and i noticed a "?" next to it on the screenshot - someone who knows win things and techpowerup may have some ideas.
I noticed the OpenCL tickbox was also clear.
freestman, could you update
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freestman, could you update GPU-Z to new version please. There's been many fixes. Let's see if 2.5.0 will show identical information.
https://www.techpowerup.com/download/techpowerup-gpu-z/
That "?" next to Bus interface information is just a box leading to an inbuilt Render test.
The other same model card is
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The other same model card is on different machines
https://einsteinathome.org/host/12440971/tasks/0/0
6xxx seconds per task
AgentB wrote:PCIe x8 may be a
)
These days, I have a number of dual GPU setups, both RX 460 and R7 370. I take care to 'match' the GPUs - same brand, same model. The motherboards have x16 slots that are x16, x4 electrically. The first thing I noticed was that the device that BOINC identified as device 1 was a bit faster than device 0. I assumed that device 0 would be in the x16 slot and device 1 would be x4 -- obviously not, so it would seem.
The difference wasn't all that large, particularly with Polaris, so I didn't investigate further. The worst case I recall seeing was with dual R7 370s with both devices running GPU tasks 2x (4 GPU tasks all up). Device 0 was reporting crunch times of around 37 mins and device 1 around 33 mins.
Presumably PCIe x8 should be less of an issue than PCIe x4 and might contribute to a slowdown but perhaps not the variability of any slowdown.
Cheers,
Gary.
The same card is on different
)
The same card is on different machines
https://einsteinathome.org/host/12254525/tasks/0/0
6xxx seconds per task