Over at the Pro Tools forum, they have a test called the DaveC test (so named for the creator of the test). It goes like this:
I think we could do something like this for T2, and we could mix in Mac too, just to see what the optimal combination is. Being a computer geek, I think it's really interesting as well.1) Open new PT session
2) Create a new mono audio track
3) Add PT stock effects Compressor, 4B-EQ, Slap delay, medium delay, long delay.
4) Open the System Usage window under the Windows menu item to see the CPU utilization.
5) With your mouse select the newly created track from step 2 above.
6) Press Alt-Shift-D (to duplicate the track)
7) Record enable the track.
Repeat step 6 until your CPU goes into the red.
9) If your CPU is in the RED delete the last track created. IF it's still in the red, delete another track until the CPU is back in the green. Click on the CPU meter after every deletion to reset the meter (see warning below). Going into the RED means your getting a -9128 message from PT.
10) Hit RECORD, and record for 60 sec. (it doesn't matter what you record as the file still get's created). If your CPU goes into the RED then delete a track and repeat step 10 until you can record 60 secs. without peaking.
So I guess the key thing is to use the stock plug-ins, that way everyone would have the same tools to replicate the test. So the question is, which ones?
I'd say to go along with the DaveC, but add in a reverb as well.
It should be easier to do this test too, since T2 is easier to use than PTLE!
What does everyone think?
For instance, I'd be contributing a 1.33Ghz Celeron laptop test, an Athlon 2500+ desktop test, and a desktop Sempron 64 3000+ test (friend's machine). All of these have different chipsets and memory amounts, and also different HD types and speeds.

