Acer computer freezing after booting...

This isn't actually my computer, it's my girlfriend's. She's been
without antivirus software for a couple of weeks now, and the computer
is connected to a constant internet connection. The computer is rarely
turned off.

This morning she called and asked if I could come out and take a look
at the computer, and I did. At first I could get it to boot, and get
past the Welcome screen (Windows XP, here), but once the Desktop had
loaded, the mouse and keyboards froze, and the hourglass icon stayed
put on the screen exactly where it was before it all froze up. I
restarted the computer, and this time it wouldn't even let me use the
mouse or keyboard on the Welcome screen, so I couldn't log in. I
killed the power and started the computer back up a few times,
unplugging unneeded USB devices and moving them around. (The mouse and
keyboard were both USB.) After that didn't work, I swapped the mouse
for a PS2 mouse. It worked, but the machine still froze after logging
in.

I booted up in safe mode, and got logged in and to the Desktop...
Everything worked fine, no slowness or freezing whatsoever. I opened
up the previous antivirus program that was on the computer before the
license expired, and ran a full system scan. (Why does that still work
after the software has expired?) I also defragmented the only hard
drive with anything on it, the other was empty. The hard drive was
very very fragmented, it took a long time to finish defragging. So, I
left with the virus scan and the defragging still running. After the
scan and defrag finished, the computer was turned off, and then turned
back on.

The screen remained black and did nothing at all, though the cooling
fans blew steadily.

So now I've got a Memory Diagnostic boot disc, and soon I'll have the
"Ultimate Boot CD" from a the website that led me here, both
of which I'll be trying in the morning.

Any ideas on what could be causing all of this?

Narrwald wrote:
> This isn't actually my computer, it's my girlfriend's. She's been
> without antivirus software for a couple of weeks now, and the computer
> is connected to a constant internet connection. The computer is rarely
> turned off.
>
> This morning she called and asked if I could come out and take a look
> at the computer, and I did. At first I could get it to boot, and get
> past the Welcome screen (Windows XP, here), but once the Desktop had
> loaded, the mouse and keyboards froze, and the hourglass icon stayed
> put on the screen exactly where it was before it all froze up. I
> restarted the computer, and this time it wouldn't even let me use the
> mouse or keyboard on the Welcome screen, so I couldn't log in. I
> killed the power and started the computer back up a few times,
> unplugging unneeded USB devices and moving them around. (The mouse and
> keyboard were both USB.) After that didn't work, I swapped the mouse
> for a PS2 mouse. It worked, but the machine still froze after logging
> in.
>
> I booted up in safe mode, and got logged in and to the Desktop...
> Everything worked fine, no slowness or freezing whatsoever. I opened
> up the previous antivirus program that was on the computer before the
> license expired, and ran a full system scan. (Why does that still work
> after the software has expired?) I also defragmented the only hard
> drive with anything on it, the other was empty. The hard drive was
> very very fragmented, it took a long time to finish defragging. So, I
> left with the virus scan and the defragging still running. After the
> scan and defrag finished, the computer was turned off, and then turned
> back on.
>
> The screen remained black and did nothing at all, though the cooling
> fans blew steadily.
>
> So now I've got a Memory Diagnostic boot disc, and soon I'll have the
> "Ultimate Boot CD" from a the website that led me here, both
> of which I'll be trying in the morning.
>
> Any ideas on what could be causing all of this?
>

You can also get a bootable hard drive diagnostic, from the disk
manufacturer's web site.

If you're no longer getting video, check the cables. Have a look inside
the computer, for things like leaking or bulging caps. Check that
everything is seated, all cables tight etc. My rule of thumb, is
unplug the power, if you plan on pulling and reseating RAM or
plug-in cards, or cables. When the back switch is on, there is still
+5VSB flowing, and power is derived from that to run the RAM slots.

I think you'll know pretty soon, whether there is a hardware problem.
As soon as you try some of your alternate boot ideas. When you
switch on the computer, you should also listen for beep codes,
assuming the Acer uses that concept. Either a piezo device on the
motherboard itself (black disc the diameter of a quarter and about 3/8"
high), or the computer case could have a speaker mounted inside it, to
make the beep. A single short beep at the beginning of POST, is a
good sign.

Paul