I have an old 2005 HP Pavilion, running windows XP. I am a beginner at computers for the most part, but I have done some research.. mostly though I'm ignorant. I know I can get into the bios, but I can't get XP to boot... not in safe mode, can't even get to system recovery. It's like the hard drive isn't there any more. I think a trojan crashed it. No noise, not a hard drive physical problem. I can still get to the BIOS, presumably because it's not on the hard drive? I don't have a boot disk, just system recovery disks. It gets to a black screen with a mac os address with some numbers I think and a blinking cursor that won't let me type anything. Never had a BSOD or anything, it just started throwing errors and I rebooted it a couple times trying to fix it with some malware programs and lost programs each time I rebooted, and then the next time, it went to this black screen.I would really appreciate some help. Thanks!