If you ever cleaned inside of your computer (as you should, once in a while), you may want to read this:
http://www.technibble.com/computer-killers-pet-hair-dust-and-cigarette-smoke/
Not always everything is visible at first glance.
...and I was surprised myself, seeing what simple cigarette smoke can do:

But, watch out for this guy!



I've seen worse. Try a dell that sat in the same place for FOUR years in a guys apartment that was literally NEVER dusted. Try an IBM that sat in a dusty office for about that time and had a mat of dust under the drive, or, try to imagine a computer so riddled with Cigar smoke that though it once was white, it was now sticky and yellow. Everything inside was coated with the same RESIDUE, every fan was froze up from it, the PSU, CPU, and motherboard fried due to the fans freezing up.

I've seen worse than that though, seen one of those AMD systems with a CPU built onto the motherboard with so much dust on the CPU heatsink that the fan couldn't spin, fried the CPU. Seen a sony vaio P3 systems with dust cycles hanging from it, and yes, I've seen heatsinks and even fan vents coated in more hair and dust that the Intel heatsink in that picture Broni.

Has anyone ever opened a computer to the smell of fried components, cigar smoke, burnt fur/hair, and burnt dust? I have, nearly threw up, was worse than ten day old roadkill on the highway. That once white case was COMPLETELY yellowed from the sticky smoke and crap, I put on plastic gloves before I touched it. The owner actually took offense to that. Trust me, just working in a PC shop for a few months made me want to never see another end USERS machine.Yep - they can get gross, particularly with smoking.I've had to change out the CPU fan on one of my client's PCs every six months because he smokes near the computer so much...There was also a case on this board, where CD drive didn't want to read disks. After some investigation, it was full of cats hair.Oh, the cat hair CD drive thing reminds me... The cigar residue glued the CD-ROM drive and CD-RW drive SHUT on the computer. I'm willing to bet it ruined the lense too, oh, power button was stuck in the on position also. That's why he brought it in, he said "The power switch is stuck so it won't turn on.". Didn't take me two minutes to realize that's not why it wouldn't turn on once i got the side panel off... But yeah, computers need to be babied, 'else they grow cancerous forms of everything floating AROUND your house, oh, and a friendly note, dusts compositio is over 90% human dead skin, and animal dead skin too.