horizontal lines on imac trouble, and smcfancontrol seems to fix IS THIS SAFE?

[vegas-steven]

Ok, sorry for the caps in the title...

i have an older imac, the first core 2 duo imac that came out (2.0ghz and an ati 1600 card in it)
since leopard i have the same problems as alot of other people however i just recently found out that it was heat related and so since the machine is pretty damn old i am way out of warranty even if i had applecare for 2 years (computer was bought in september of 2006)

so i downloaded smcfancontrol and am running it at these settings:

ODD: 1506
HDD: 1729
CPU: 1494

so far there are NO LINES, and very very few other hiccups.
this was causing alot of issues as the computer would sit and idle, and eventually it would need to be reset.

is this safe? i dont want to destroy my fans.

anyhow, the other question seeing as i live in the desert is. how much dust builds up in these computers?
should i consider dissasembling it and cleaning it out?

and will apple just laugh at me if i ask to have it fixed at a reduced rate or anything like that?

i mean, this was their update that broke my computer.

 

[Passive101]

Taking it apart with a can of compressed air can work wonders. Since it does appear to be heat related as faster fan speeds are getting rid of your graphical issues I would definitely say to clean it.

 

[vegas-steven]

i almost wonder looking at istat pro how much of this is really gpu related.

i ran an HD feed from hulu of heros in full screen with the istatpro widget on the dashboard in realtime, and i watched the cup run from 48C up to 57C, as the GPU diode temp only ran from 60-62

i need an idea of WHERE the gpu is.
i would love it if there were a service manual of this machine, but i would bet that apple doesnt have one available like most other computer manufacturers.

btw, i had the fans faster for that test i just mentioned, set at:

ODD 1961
HDD 2280
CPU 1941

i figure the cpu isnt under much load unless i am doing something with imovie or whatnot, and that the HDD is constantly moving, so that is where i settled on those numbers.

The ODD was set before i realized that it means optical disc drive. being that, it doesnt matter the speed as much.