Yes, it could. Even if you only use the firewall, some more general processes are activated. One of the features of avast is that it does here and there launch "test files". And my guess is it's what causes the problem you experience

I would advise you to either use Comodo and only Comodo , or to pair Avast with another firewall ( Online armor is perfectly compatible )

Thanks I didn't know about Event Viewer. I'll check it later as I have to run now, and hopefully find the source of the problem. I'm really hoping it's just a software prob.
Interesting, I had no idea there was such a firewall called Online Armor. I did some research, and apparently it's not included in the latest Matousec's HIPS test. Digging deeper revealed that Matousec's test is not to be taken seriously, and apparently there was some falling out between them and the developers of OA resulting in OA being taken off the HIPS test. It's also said on the Wilders Security forums that OA is one of the best firewalls in the market. Can anyone here testify to this (or against this)?

Looooooool you guys aren't going to believe this, but I think this is the root of the problem. 2 out of 2 times, when I have it on, the PC hangs. Without it nothing happens for a few hours. I'm trying to figure out why it's making my PC hang though, since nothing happens on my other PC (which also has similar software installed).

I wish I could help Lowy, but, I got nothing..If it makes you feel better I had a PC that died prematurely about a year ago...So, I feel for you man. Best of luck in getting it fixed.

Thanks mate. It's annoying because this is my first Gigabyte mobo, and I'd hate for my first experience with GA to be a bad one. Should have gone with MSI...

Well that's quite odd, mine (that died) was a Gigabyte too...Won't buy them again myself anytime soon. I replaced it with a cheaper Asus, so far, so good.

Swap the PSU with another. Hopefully you have an old one sitting around, or can swap one with a friend (a double-swap would be ideal: him using your suspect PSU and you using his known-good one). Other than that, inspect for bulging capacitors on the motherboard. Doesn't happen near as often as it did maybe 8 years ago, but that is a natural death for that particular type of component. I'd be surprised to see it on such a new board, however. But hey - eyeball inspections don't cost anything...

Avast Anti-Virus and Comodo Firewall perfectly coexist together for few years. Just don't use two antivirus monitors together.

So after weeks of monitoring, I've found out that it's actually fan-monitoring software that caused the problem. I had MSI Afterburner installed, and recalled that there was a time when Speedfan would cause my other PC to lock up all the time too, so I uninstalled Afterburner. Lo and behold. It hasn't hanged since then.

My question is, why? I need MSI Afterburner to control my GPU fan. I hate to leave the fan control speed up to the default settings.

I believe the alternative to MSI Afterburner is EVGA Precision. I haven't personally used it, but you might want to check that out. I doubt that Rivatuner is going to be a viable option at this point.

Personally, I don't mess with such things, but it's probably worth checking out. I'd research it more thoroughly before installing it though. From what I've seen of the site it looks reliable.