how to enable crossfire on a asus 88TD-M w/onboard 4250 hd & PCI 6670 HD
Hi, can anyone tell me if its possible to enable crossfire with a asus M4A88TD-M EVO with an onboard radeon 4250 hd and a pci saphire radeon 6670 HD? all the hardware is crossfire compatible and im using fglrx 11.8. Thank you.
I would be surprised if it worked, since the two GPUs are so far apart in capabilities.
IIRC one GPU has 480 ALUs while the other has 40, so the overhead of splitting work between the GPUs would outweigh the benefit you get from the second GPU. Splitting work between GPUs works best when the GPUs are identical, and you can sometimes get a speedup between 2:1 and 3:1, but not 12:1.
Thanks for your reply brigdman. I have tried to crossfire the two chips but with it hasnt worked... both chips are activated but it seems to use only the main gpu 6670. i was wondering if its possible to use both in an independent way, to use with blender cycles or slg using openCL. Is it possible to distribute the workload between them to accelerate the rendering calculation of this two rendering programs, without the two chips being directly associated?Thank you.
It is possible to use CrossFire (AMD now prefers to call it "Dual Graphics") the 6670 with Llano integrated graphics (A4, A6 and A8 series) on socket FM1 mobos. The 4250 IGP can only be crossfired with a 2400 or 3450 afaik.
Even if CrossFire is not supported, the two GPUs can still be used together with SurroundView.
Hi chithahn, thanks for your reply. As you mention on your answer thats how i actually manage to keep the to cards active, with surround view. but im only using one display. So 4250 is not actually in use. Somehow the ACCCC dosent identify the card properly it detects as active but dosent name it correctly, but under the cmd line aticonfig -lsc the card is identified correctly.
My question is :" is it possible to activate both cards to work on parallel (to distribute the workload) on rendering processes under blender/cycles|SLG , using openCL ?"(slg allows you to use multi openCL plataforms)(multi openCL o/i). At the moment the card is not used at all ...neither by slg (wich states that only cpu and turks is in use), glmark only uses 6670HD. Thanks for your time.
I would not care about the slow onboard gfx when you already have got a better card. most likely it just consumes extra power without additional gain. Better disable it - should be automatically if not forced on in the bios.
I agree with Kano about disabling the Radeon HD4250. The main reason being that the Application SDK for OpenCL on linux is unavailable on the onboard graphics until the Radeon 6000 series ( in particular the APU chips ).
Thanks for both your answers. nevertheless i have one last question... since my desktop becomes laggy after running rendering on slg gpu rendering v2(and cycles gpu rendering), would it be possible for the 4250HD to draw the desktop and the 6670HD used only for the rendering?Thanks for your patience.