Real weird computer problem(s)....

Well, lately I have had my computer just turn off on me. Like just a few minutes ago, I was on the computer (computer was fine, no lock ups, not overheating, etc) and then it shut downs, give me a black screen (like if it turn off). But on my computer, the green "on" light turns off and the orange "hdd loading/activity" light is on (not blinking, it's just on).

I've done a virus scan earlier (reported nothing bad) and my computer has been fine lately, but it'll just randomly shut down (like turn off) but the orange hdd loading light will then appear just "ON" without any blinking (like if it was loading anything). Since I can't it to go back into Windows, I have to restart the computer by hand.

My computer is updated to XP SP2, Ram isn't an issue, but I'm guessing it might have something to do when I was using TuneXP the other weekend.

Also, I got another problem where when I turn on my computer, it will sometimes not load up and will just give me a screen with a dash "_" blinking. For this I have to go into the bios settings, UNenable the IDE connection, restart the computer again, go back into Bios and REenable the IDE connection, so it can boot up off my C: drive.

Anyone know what I could do to fix these problems?

Thanks

 

Since I don't know how to edit the last message, I'll add in that I'm running off a HP Pavilion 503w, 1.8 ghz Celeron, XP SP2, 80 GB + 40 GB HDD's, 384 MB RAM, and the floppy disk drive was removed for cooling reasons.

 

I personally think that's an HP issue as my HP Pavillion has done that to me before too.