I am having worse problems with my Dell mini (Inspiron 910) running XP home edition! Could be malware, software, or hardware, but bottom line is it keeps freezing (sometimes even at desktop with nothing running but Avira Free), and I have to turn it off and on. I'll give you folks as much info as I can:
The medical history: Had computer since last summer. Noticed pretty soon that it seemed to have a tiny bit of a memory drain, which has grown worse. It only had a 7 GB drive to begin with, and most of that was filled up with system and other stuff. Things had been slowing down before any malware detection anyway. FWIW, got hit by Security Tool virus a couple months ago but a Dell technician cleaned everything out for me remotely (checked registry, too) and that problem seemed to disappear immediately.
Then, over the last couple weeks, started getting many VM too low error messages (used to get them long BEFORE the Security Tool virus, too). At same time disk space had dropped to 900 MB or lower. As I said, the disk space had been dropping for some time; couple months ago I threw away everything I didn't need, had 1.2 GB free, but by now it's dropped by 600 MB and I've hardly added anything!
In the last couple days things started crashing, then freezing up. Prior to any new malware detection, there were crashes in Firefox (can't remember now if there were freezes).
Then yesterday Avira free detected a virus (Rootkit trojan) and I "denied entry"; when it gave another warning a few seconds later I deleted the Temp file that it said was infected.
Since the virus detection, I've had to turn computer off a number of times to un-freeze it. Skype (audio only) gets disconnected, and any multi-tasking online (more than one program open, or more than a few tabs) seems to cause freeze or crash.
Avira scans and Malwarebytes scans all turned up negative after that. Just to be sure, I downloaded SuperAntiSpyware; it detected a Trojan in two Registry files (threat level 5 out of 10), but SAS was too big to run so I had to uninstall it; also, more subsequent scans with Malwarebytes and Avira (and online quickscan with BitDefender) all found nothing, so I thought these might be false positives? Anyway, quarantining them didn't help, so I put 'em back in Registry, not knowing what they were for and knowing not to mess with Registry since I really don't know squat about the registry..
At the same time as I've been having these problems (before yesterday's virus detection) I noticed the CPU usage was really high at times.
Observed from Task Manager:
"avgnt.exe" and "avguard.exe" (both for Avira) between em use about 140,000 K.
"services.exe" occasionally jumped to 50% CPU
"firefox.exe" jumped once to 40% for no apparent reason while I was watching (most of the time it was negligible)
Many many spikes to top of CPU usage history screen; CPU jumps to close to 100% at times, then when computer freezes drops to zero
Current free disk space - just over 600 MB
Pagefile size - Initial 400 MB, Maximum 600 (rec: 1521)
The only thing that is consistently added to computer are Avira updates. The Avira folder size has bloated to 125 MB! Keeps updating itself, and recently the updates briefly freeze things. Takes longer suddenly for Avira to load (umbrella takes long to open, to the point that I get a warning from Windows Security until it does open)
Ran Windows Diskcheck, and it found no problems. No need to Defrag volume, according to Windows.
Now I can hardly use this computer (at times it behaves for a while, like now..)
So was the malware just a coincidence that isn't the real problem (in which case problem is probably low memory), or is it adding to the problem? Or was it already an undetected problem? [Or did the tiny drop or two of water that fell on the keyboard (REALLY minimal) the other day have anything to do with it?? :o] I have no idea. Now I can't even burn that CD I had just asked you all about...