What to fold with only one of two GPUs

[Christopher_Ambrey]

Hello fellow Folding@home users ,
This is my first post on the Folding@home support forum. I'm still relatively new (less than one year) to Folding@home. I have two GPUs and I want Folding@home to just use one of them. Under Configure > Slots > I have removed the additional GPU and the CPU, I only have one GPU remaining. I have edited this so that the GPU-index = 1, opencl-index = 1 and cuda-index = 1. I have pressed okay, saved the changes and restarted the computer only to find that the GPU-index has reverted to -1 and it is once again using the Geforce GT 610.

GPU0 (Folding@home) GPU0 (GPU-Z) GPU0 (FAHClient.exe –lspci) PCIe x16_1 (physical motherboard location) Geforce GT 610
GPU1 (Folding@home) GPU1 (GPU-Z) GPU1 (FAHClient.exe –lspci) PCIe x16_2 (physical motherboard location) Geforce GTX 750 Ti

I was sure I was correct by declaring the following under the slot option: GPU-index = 1, opencl-index = 1 and cuda-index = 1. It seems to recognise it when I do this in the client on the face of it. But judging from the temperatures in TThrottle for GPU0 and GPU1 (and the very slow progress) it is actually stubbornly using GPU0 (Geforce GT 610) rather than GPU1 (Geforce GTX 750 Ti). When I reboot, as mentioned above the client just goes to GPU-index = -1, opencl-index = 1 and cuda-index = 1. The client acknowledges only the GPU0 Geforce GT 610 when it comes to processing work units and recommences (usually with a new work unit ) the very slow folding. I'd really welcome any assistance anyone may be able to offer to help me resolve this problem.
Chris

Further details about my system and situation...
SLI is disabled.
GPU-Z has ticks for OpenCL and CUDA for both GPUs.

Computer Specs:
CPU: Intel i7 CPU 950@3.07GHz
4 cores 8 threads
Memory: 12GB DDR3
Motherboard: ASUS P6T
Power Supply: 550W
OS: Windows 7
GPU0: Geforce GT 610
GPU1: Geforce GTX 750 Ti
Network Connection:
ADSL
Wireless network adapter in PCIe x16_3 slot
Overclocked?:
There is some automated overclocking controlled by the motherboard up to 3.2GHz or so. The CPU has a closed loop water cooler. There are plenty of fans in the case too (I can't fit any more in).
Stable?:
Without Folding@home running my system seems stable. It's still a bit of an open question as to whether or not the system is stable running as I would like it to be. The PC is stable overall.
Software:
I am using version 7.4.4 of the Folding@home client. I also have BOINC running and configured to use the Geforce GT 610 and some of the threads (87.5% of the CPU resources, 7 threads), leaving one for the GPU I hope to use with Folding@home. I am not running BOINC for the moment though, while I try to get Folding@home to use the right GPU.
WU details:
I'm not sure what to put here. I'm hoping Folding@home will recognise my desired configuration for this computer and send me the appropriate work units. Preferably something I can complete in a 12 hour interval or something that will allow me to save the progress I've made. While I would like to leave my computer running longer, I can't.

[Christopher_Ambrey]

I should also add to the above description that I am only running the one monitor (from the Geforce GT 610 graphics card) while the Geforce GTX 750 Ti card doesn't have a monitor attached. I read in a few places (including from memory on the Folding@home website) that with Windows 7 this may be an issue. I have sought out a DVI-I 'dummy plug' for my Geforce GTX 750 Ti. I will report back on whether or not this resolves the problem. I've ordered the the dummy plug online so it may take a little while to get to Australia .

[ChristianVirtual]

Welcome to the forum Christopher_Ambrey,

"messing" with the indices can be painful; not having myself lots experience with it.

But as long someone with more knowledge jumps in, here an easier workaround:
1) just let the client create both GPU slots, set an slot option "pause-on-start" to "true" for the GT 610 (you can set that actually for both slots, if you like). Also set that option from the CPU slot in case you don't want to process CPU projects.
2) un-pause only the slot with the GTX 750Ti and start folding; make sure to use the right-click on the slot to start and NOT the big button on the upper part of FAHControl.

As for the DVI-dummy plug, not sure. Works well under Linux without any need to attach anything. Does your monitor by chance support two inputs ? Just connect a second cable ?

Hope that helps a bit until better hints coming up.

[toTOW]

I think Windows doesn't need dummy plug anymore (last time I has to use some were with Vista), but Linux might still need them (but I don't have any experience with it).

[bollix47]

No dummy plugs required for Linux either.

The key is to make sure all GPUs are physically in the computer when installing the drivers and folding@home. There should be no need to fiddle with indices if done correctly and in that order.

If you want to uninstall F@H to give the above a try make sure you "Finish" any work in progress first and then uninstall F@H and check the box to remove Data too or delete all F@H folders. You want to ensure there's no previous Folding configuration database files that are normally kept in your Data Directory/work.

[artoar_11]

My advice is to use GT 610 only for the monitor. Very slow card, Fermi architecture.
GT 610: Cuda cores - 48; MEM - DDR3/64 bit.
"The GeForce GT 610 card is a rebranded GeForce GT 520."

[7im]

The 610 would fold core 15 work units very well, if you wanted to fold on both cards.

Unless you set the indexes correctly (as pulled from GPU-Z or the like) the indexes will return back to default -1.

The easiest fix is to allow both GPU slots to be installed. Then simply pause the GPU slot for the 610. That's it. Then only the 750 will fold.

[Christopher_Ambrey]

Hi Everyone,

Thanks for you all for the quick responses. I'm happy to report that setting a slot option "pause-on-start" to "true" for the GT 610 worked perfectly. Also, it seems I won't need the 'dummy plug'. Thanks again for your help .

Chris