i don't know why changing the power supply would have any effect unless your computer was overheating. you really need to scan with 2 or 3 spyware scanners to have a good chance of removing everything. ask Compaq if they have a program to monitor the temperature of the CPU and see if it is slowing down because of overheating. bring up Task Manager and look under Processes. sort by CPU consumption to see what's on top.

Herb....