Somewhere around the massive Jan. 10th Microsoft update, my computer began acting strangely. Pushing the power button did nothing, and I had to unplug it, wait, then plug it back in for it to start. Once it is up, it runs perfectly, though rather slow, but it's an HP Pavilion (4GB Ram, Intel Quad 2.66GHz, GForce8500GT, Win7 64 bit), five years old, and yes, I'm looking to replace it.
In the meantime, I've tried: Changing power cords, changing electric outlets. scanning for virus, removed some extraneous programs, Event log reading, plus Googled this until the cows came home. Then I took it to a local computer shop where they had installed a new 450w PSU in September and they checked the motherboard (OK), replaced the CMOS battery, and even replaced their installation of the PSU with a new 450w model. Although they duplicated the problem, they couldn't solve it. I brought it home. I called HP and their customer care told me to unplug the computer from the back of the CPU, hold down the power button for 30 seconds, then re-plug and start. It started, but though he assured me it was fixed, it was not. Once it cooled down, I had to repeat the unplug/plug process to turn it on.
I'm backing up everything on this computer, and it's still working perfectly, but I wish I could solve the power problem. At this point, as you can imagine, I'm willing to try anything and everything, and I would really appreciate any suggestions you all have. I've poured over this forum for any other situations like this and am stumped that no one else has this problem.
Thank you very much.