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). If I plug in AC power the system immediately jumps back to normal. Pull out AC power and system resumes its crawl, andCPU 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 offall screen saver and battery management options but these had no effect. Any suggestions? If I never use the battery I can live with the performance, but what is triggering the 100% cpu utilization when I switch to battery mode?