My HP Pavillion a400n power light flashes but computer will not power up or boot. Is it possible that I got a virus? I had Norton installed on it and the other computer which s hooked up to it via WIRELESS is still working with no problems.If it won't power up at all its definitely not a virus but a hardware issue. What happens when you press the power button? Does it make any noises like fans or harddrives spinning up or is it just dead?I would recommend checking and testing the Power Supply Unit,
take the cover of try and boot check out any fans see if they just twitch, check out the exhaust fan from the PSU see if it actually works,

if a replacement PSU is required, measure the dimensions of the one installed, as sometimes in HP, Compaq and Dell they are smaller than a standard unit and may require ordering in.I had a very similar problem just the other day at work I had a Dell Optiplex that wouldn't boot up instead the power button just had an amber light flashing, so I contacted Dell SUPPORT and they told me my PSU fan wasn't working. (i'd already tested the PSU and the voltage was fine and the memory was fine) so I took it apart and opened up the PSU and checked the fan and it was working fine. So I got back on chat with Dell support and halfway through our conversation the computer just booted up all on it's own for some odd reason... it's been working fine ever since. I have no idea what was wrong with it or what fixed it, it just worked. lol so all that to SAY it sounds kinda like the problem I faced but I don't know how to fix it. I guess this was more of a sympathy post. lol Make sure the PSU is working properly and the memory is seated well.Quote from: Deerpark on July 19, 2007, 03:49:32 PM

If it won't power up at all its definitely not a virus but a hardware issue. What happens when you press the power button? Does it make any noises like fans or harddrives spinning up or is it just dead?