Vista jumps to 100% cpu when switching to battery mode

[contracts]

I am running Vista Home Premium (which I upgraded several months ago from the Vista Basic that came installed on my Acer 3680-2022). This laptop has 1.5 GB RAM.

After any full boot the system will crawl if it is running on battery (and I do not know if this is the culprit but csrss.exe is doing plenty of I/O Reads during this time). If I plug in AC power the system immediately returns to normal responsiveness. Pull out AC power and system resumes its crawl, and CPU becomes 100%.

If csrss.exe is the culprit (note that this does not appear to be a trojan/virus version of csrss.exe) then exactly what is it doing after every cold startup? And while it is running then why does my system crawl (as in the general system response goes from 1 second to 30 seconds for everything) when I switch to battery mode?

I also have tried turning off all screen saver and battery management options but these had no effect. Any suggestions? If I never use the battery then performance is fine, but what is triggering the 100% cpu utilization when I switch to battery mode?

And if csrss.exe is the culprit how can I track down what initiates csrss.exe?

[Boris]

Have a look here ? :-

http://www.joryanick.com/fixingCSRSS.htm

[contracts]

Boris

I think your "disable power management" reference at http://www.joryanick.com/fixingCSRSS.htm addressed my problem. Although I had tweaked my "High Performance" power profile to never turn off the display nor the system, I had neglected to actually select that "High Performance" radio button - hence I was still running with power management in effect.

Apparantly your referenced article was right on and Vista on my laptop ended up spending so much time trying to be power efficient that it was "black hole-ing" my system's resources. That paradox obviously doesn't make sense to me from an engineering view but at least by completely disabling power management that seems to be an effective workaround. Thanks!