I'll try to give as much information as I can.
This morning I ran an Avast virus scan and it detected two files which it put in the "chest." It suggested a reboot, and something about an additional scan. I do not remember the files tagged nor the scan it suggested. I rebooted since it all seemed reasonable. Upon reboot, it never got to desktop. It didn't get anywhere, splash screen, Windows logo, nothing. After many minutes, I held the power button to manually shut down. This has happened a few times in the last six months. But it always worked again after turning back on (post manual power down). But now it didn't. I tried several times, same thing. I even left it on for over an hour thinking maybe something is happening in the background, but nothing. No clues or indications as to what is wrong. Always a black screen. No mouse cursor or anything. Monitor says it isn't getting a signal.
I did research all day on the topic. I tried getting to a "safe mode" or to BIOS by tapping function keys. No avail. I tried booting with the Windows 7 recovery DVD I got with the computer. Nothing. I tried unplugging the battery for 15 minutes to clear memory. Nothing changed. Tried replacing the battery. No luck. After unplugging and plugging back in the battery to clear memory, the problem seems worse, actually. Now, shutting down the machine requires simply pressing the button rather than holding it. There are no unusual sounds from the machine. Power lights come on as expected, fans hum and I get a single beep. Nothing after that. I tried another monitor, different cables, nothing appears in any combination. Always a black screen.
I'm about out of ideas. Any advice? I've been able to solve many PC issues with the internet's help, but this one has me stumped.
Windows 7, Alienware X51. If more detail is needed, I can provide.
Thanks in advance!