multi GPU slower then single GPU ?

[ribrahomedesign]

Hi there .
i just noticed that with my new scene ,rendered with pathtracing ,multiGPU is slower then one GPU ?
i have two identical GTX 285 and both connected to a PCI Expressx16 Gen
is this because its pathtracing a interior shot ?
thanks
Rico

[radiance]

this is usually because you have SLI enabled.
switch it off in your nvidia control panel...

Radiance

[ribrahomedesign]

Yes SLI is enabled ,but if i disable SLI , octane only recognice 1 GPU ?
Rico

[Amplitude]

disable sli but try with physX enabled

[ribrahomedesign]

i am sorry but i was wrong ,i dont have SLI ,but PhysiX is enabled ,if it is disabled octane does only recognice 1 card.
thanks
Rico

[radiance]

i am sorry but i was wrong ,i dont have SLI ,but PhysiX is enabled ,if it is disabled octane does only recognice 1 card.
thanks
Rico

are you sure there is no SLI option in your nvidia control panel ?
lower performance with 2 identical cards is 99% due to having SLI enabled.
(even without any hardware SLI connectors/bridges)


Radiance

[ribrahomedesign]

yes, i have no SLI option ,i dont know why.on my older machine with 2x 8800GTX i have the SLI option
shouldnt i have the SLI option on my new machine ?
regards
Rico

[radiance]

yes, i have no SLI option ,i dont know why.on my older machine with 2x 8800GTX i have the SLI option
shouldnt i have the SLI option on my new machine ?
regards
Rico

no idea....
maybe try installing the latest drivers from the nvidia main page ?

Radiance

[Amplitude]

what board are you using? maybe your chipset doesn't support sli at all... (which is irrelevant for octane anyway)?

[ribrahomedesign]

i dont know what board i have ,
i have a look if there is a new driver available
thanks anyway.
Rico