I have a dedicated cruncher that has been running a GTX275 for months. I just picked up an 8400GS for nothing. However, when I added it to the PC it is not being used. I read some other posts about rolling back the driver to 301.42 so I did that. Any other ideas? I have never had to tweak anything serious before... Here is my log file.

6/8/2013 10:29:55 PM | | No config file found - using defaults
6/8/2013 10:29:55 PM | | Starting BOINC client version 7.0.64 for windows_intelx86
6/8/2013 10:29:55 PM | | log flags: file_xfer, sched_ops, task
6/8/2013 10:29:55 PM | | Libraries: libcurl/7.25.0 OpenSSL/1.0.1 zlib/1.2.6
6/8/2013 10:29:55 PM | | Data directory: C:\Documents and Settings\All Users\Application Data\BOINC
6/8/2013 10:29:55 PM | | Running under account admin
6/8/2013 10:29:55 PM | | Processor: 2 GenuineIntel Intel(R) Core(TM)2 Duo CPU E8400 @ 3.00GHz [Family 6 Model 23 Stepping 6]
6/8/2013 10:29:55 PM | | Processor features: fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss htt tm pni ssse3 cx16 sse4_1 nx lm vmx smx tm2 pbe
6/8/2013 10:29:55 PM | | OS: Microsoft Windows XP: Professional x86 Edition, Service Pack 3, (05.01.2600.00)
6/8/2013 10:29:55 PM | | Memory: 1002.34 MB physical, 4.87 GB virtual
6/8/2013 10:29:55 PM | | Disk: 74.53 GB total, 55.19 GB free
6/8/2013 10:29:55 PM | | Local time is UTC -4 hours
6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, CUDA version 4.20, compute capability 1.3, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, CUDA version 4.20, compute capability 1.2, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 307.90, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 307.90, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)

Thanks,
ChuckBens

Boinc will only use the most capable GPU by default, to enable use of it you need a cc_config.xml with the <use_all_gpus> option enabled:

Client_configuration

The next question is why is OpenCL being detected twice for each GPU:

6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, CUDA version 4.20, compute capability 1.3, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, CUDA version 4.20, compute capability 1.2, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 307.90, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 307.90, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)

Claggy

The next question is why is OpenCL being detected twice for each GPU:

I think a driver sweeper session is advisable:

6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, CUDA version 4.20, compute capability 1.3, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | CUDA: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, CUDA version 4.20, compute capability 1.2, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 301.42, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 301.42, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 0: GeForce GTX 275 (driver version 307.90, device version OpenCL 1.0 CUDA, 896MB, 834MB available, 1037 GFLOPS peak)
6/8/2013 10:29:55 PM | | OpenCL: NVIDIA GPU 1 (not used): GeForce 8400GS (driver version 307.90, device version OpenCL 1.0 CUDA, 512MB, 494MB available, 30 GFLOPS peak)

Gruß,
Gundolf

I have no idea how to do either one! I can create the config file with a text editor. Is that the only entry I will need?

I know I am using a couple of older drivers, but I have had problems with newer ones on the GTX275. I read somewhere that the older driver was probably needed for the 84000 GS card as well.

I don't know what the drive sweeper is...

I'd appreciate any help getting me pointed in the right direction.

Is it even worht it to try and run both older GPU's?!?!

Thanks,
ChuckBens

Copy this cc_config.xml file into Notepad and save it in your BOINC Data directory C:\Documents and Settings\All Users\Application Data\BOINC\ as "All Files", named cc_config.xml, making sure (check visually) that Notepad didn't add a .txt extension. If it did, rename it so the only extension is .xml
Don't use a fancy text editor, don't use an XML editor, don't even use Wordpad, just Notepad. Notepad doesn't add extra characters that other editors do add.

Exit & restart BOINC to take effect.

<cc_config>
<options>
<use_all_gpus>1</use_all_gpus>
</options>
</cc_config>

(For those wondering about the exit & restart, it's a GPU decision, which can still only be done at start-up time, so re-reading the config file won't help here.)

Driver Sweeper: http://www.techspot.com/downloads/4266-driver-sweeper.html
Read the "How to use?" on that page.

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