>Denis Pelli wrote:
>
>> dear emily
>>
>> one simple thing you could do would be to run DescribeComputer,
>> DescribeScreen(0) and DescribeScreen(1). This will identify the drivers.
>>
>> best
>>
>> denis
>>

Emily Grossman wrote:

>The results from the tests you suggested running are below. I also got an
>email from Paolo Martini referring me to the forum message 485. He had a
>similar problem, and also thought that updating the drivers might help, but
>hadn't been able to test the theory because he didn't have access to the
>system anymore.
>
>The computer I've been writing about is a shared computer, so I have to ask
>permission (i.e. make sure no one is in the middle of experiments) before I
>do any updating. If updating bring resolution to the problem, I'll send an
>update to the forum.
>
>Thanks for your help.
>-Emily
>
>DescribeComputer
>
>****** blakelab's Power Mac G4/733, Mac OS 9.1 ******
>unknown PowerPC processor, 733 MHz, memory bus 133 MHz, 87.289 Mflop/s
>PsychToolbox 2.44, 7 August 2000, MATLAB 5.2.1.1421
>QuickTime 4.1.2
>FileSharing is on.
>No screen saver.
>Using UpTime-based timing, which is very accurate and reliable.
>Has serial port arbitration.
>>>DescribeScreen(0)
>*** Screen 0 *************************************************************
>NVDA,NVMac (.Display_NV version 1.0) in slot SLOT-1
>8 bit dacs. 1024x768 75 Hz. (60,65,67,70,72,75,85 Hz avail)
>>>DescribeScreen(1)
>*** Screen 1 *************************************************************
>ATY,Rage128y (.Display_Rage128 version 1.0f44) in slot SLOT-2
>8 bit dacs. 1024x768 75 Hz. (56,60,67,70,72,75,85 Hz avail)
>
>--
>Emily D. Grossman
>
>Department of Psychology
>Vanderbilt University
>Nashville, Tennessee 37203
>e.grossman@...
>http://www.psy.vanderbilt.edu/students/grossman

Dear Emily

thanks. since you are now able to run your experiments, perhaps you can
just ignore the issue. however, if you'd like resolution, i have a couple
thoughts. running two cards from different manufacturers is in principle
fine, but does, of course, offer more opportunities for problems than if
they came from the same source. video cards are quite cheap, so you might
consider suggesting the purchase of a second Rage128 card since we know
that card works well for many people (including me).

also, i'm enclosing some recent test programs that we developed here to
look at priority and timing issues. these programs may or may not crash
with your delicate NVIDIA driver, and that fact, or or their reports,
would be informative.

best

denis

Enclosure: PeekBlankingTest, WaitBlankingTest, FlickerTest
These will be included in the forthcoming PsychToolbox 2.5 release.
To unpack it, you may need stuffit expander, free, from
http://www.stuffit.com/expander/