I was just reading this thread and saw mention of dual monitors causing (or possibly) causing issues with seti/cuda, is this true?

http://setiathome.berkeley.edu/forum_thread.php?id=51368

Currently I am running a Dell XPS 400 with an Nvida EVGA 9600GT KO (512MB). I am also running dual monitors, 2 Dell 2407WFP-HC's @ 1920x1200 & 32 bit color. Computer is running a Pentium D @ 3.6 with 4 Gigs of memory and a 375w power supply.

I have many other posts on here with my problems, snow on the screen & screens going black and drivers reload over and over. I ran seti/cuda for a couple weeks before those issues came up, then it happened all the time. Video card is 'fine' passes all other tests, is not overheating etc. I have read that some of these issues can also be caused by some 'low angle' data, which is over my head.

I am curious though, will my dual monitor set-up cause issues with seti/cuda?

Thanks!

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We don't know yet. I haven't had an answer back from the developers on the other issue. Until that time we can only guess it's this or that.

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OK, I have had an answer back.

In general, when you are enabling multi-monitors using the second head (VGA, DVI or HDMI) then no, it does not affect CUDA operations. However, it will more than likely use more of the GPU's VRAM to enable the second desktop. This should not prevent Seti@Home from running, unless there is not enough memory for CUDA.

The potential problem is on cards that have got the bare minimum requirement of 256MB VRAM. These could run out of memory when the second head is enabled. Cards with 320MB and more should have no problems at all.

As for calculating how much memory is being used, consider that everything you see on screen is using memory on your card. If you like lots of animated icons and mouse pointers, they all take up memory. A higher screen resolution (1900x1650x32bpp) takes up more memory than a smaller one (1024x768x16bpp). A lower colour depth equally takes up less memory than a higher one will.

Playing DVDs, watching Youtube videos, running 2D and 3D games, running a screen saver... They all use memory on the video card and use the GPU.

Seti CUDA app in GPU memory: 200 megabytes at minimum (so it can be more!)
1900x1650x32bpp resolution: 10 megabytes. (double this amount if you run dual-monitors)
GDI usage for Your desktop: 10 megabytes. (double this amount if you run dual-monitors)

It fills up pretty quickly.

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Random question, my PSU is rated at 375w (stock from Dell), the card says it has a Minimum System Power Requirement of 400w and the Maximum Graphics Card Power is 90w, do you think i am 'under powered' and could that be causing the issues I have been having when the card is running at 100%?

Thanks!

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In this I can only speak from experience with things like that. I think what will happen is that you see unexplained blue screens of death and/or sudden automatic reboots of the system.

Also possible during boot-up of the system: if the videocard doesn't get enough power it won't start up and gives off a whistling sound. (My girlfriend's 7900 has a speaker on board to do those things. Very discomforting when heard for the first time! ;-))

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