Of the hundreds of computers I have worked with, almost all of them left my care "retired" (aka: so old they hit the dumpster), sold, or given away. Well that or I left the job before they croaked
Under my watch and care I can only recall...
4 power supply failures
7 video cards
12 Motherboard failures...but I am not counting those in which we tormented by over clocking....or those in which the computer was dropped and the MB cracked (gah! that user drove me crazy! who "accidentally" pushes their computer off of their desk three times?!?!)...nor am I counting those in which the processor blew up and took the MB with it.
14 CPU failures (4 Intel, 10 AMD...however /all/ of the AMD's were those really crappy K6-2's that were notorious for overheating and blowing up...they have my vote for the worst processor in history!)*
I gave up trying to count hard drive failures...I am not counting ones that were DOA either cause bad shipping can ruin anything...
I honestly believe it to be 40 or so..probably higher... and I kid you not I am willing to bet large sums of money that if you remove Maxtor** from that list of drive failures I maybe have had a dozen or so drives die on me...
Network cards seem to cause me no end of grief. I have seen no significant difference between all of the brands i have used (drivers certainly, but not longevity). There is a reason why I start panicking when my stash of network cards gets low. Thankfully I know Dave
CDROM drives (all types and speeds including DVD drives, CD/DVD burners, and mini discs) probably tie network cards. I also keep a stash of them around...
Memory....jeez...I had a weekly phone call with Kingston at one point in my life...granted it was a known issue with the Motherboards in the 4sticks per 40-node cluster we bought*** and not really Kingston's fault....and Kingston replaced the bad memory with the memory we /should have/ gotten...but even removing that particular cluster out of the equation, however, doesn't drastically change the number of dead memory sticks I have seen.
I think the only thing I can think of that I have seen die in a computer more often then memory is...Fans.
In the case, on the video card, on the CPU, on the drives, in the power supply....God only knows how many fans I have seen dead. I have seen every fan in a computer die at least a dozen times. I buy replacement fans in bulk from Newegg. And that is why my vote goes to fans.
Just my experiences though....YMMV.
~Stack~
*please note, that wasn't an AMD bash. I *heart* AMD X2 processors...but if anyone was subjected to more then a few K6-2's they would agree with me.
**This is totally a Maxtor bash...way to many drive failures and an unacceptable amount of data lost...[very long explicative deleted]
***That cluster vendor wasn't in business long...especially once everyone realized he just bought from Newegg
but thats another story...