Advice on fan noise iMac i7 pre-refresh

[azza2988]

Today i was watching quite a lot of series on my iMac at full brightness and i turned the brightness down to around minimum and noticed a clicking noise i pretty sure its my fan. So i turned brightness back up towards maximum around mid way sound disappeared so lowered again and reappeared, so as stop watching videos and iMac cooling down the clicking noise started to ease.

I recorded the sound on my iphone and uploaded it, will some one have a hear of it see anything to be worried about. You hear it around 15 secs i think you probably notice a hight pitch sound also now and then thats the brightness issue because i am adjusting brightness so can tell the difference.

20100801 183435 1.m4a - 0.66MB (http://www.zshare.net/download/789034181c21d9c4/)

ps the noise here is not as worse as started since imac was cooling then when was the worse iMac was bit hot to touch

[dwarnecke11]

That sounds like your PSU.

[azza2988]

That sounds like your PSU.

i take thats really bad thing. Ill have to re-record the sound again when at its worse just really weird only makes that noise around minimum brightness and really hot imac soon as upped brightness towards maximum bye bye fan noise or what ever it is and back to normal arrh.

[dwarnecke11]

If it sounds like this, it's the PSU:

http://www.youtube.com/watch?v=jXyH1XGFFck

[azza2988]

If it sounds like this, it's the PSU:

http://www.youtube.com/watch?v=jXyH1XGFFck

thats bang on correct so looks like appointment at apple then they may as well fix my high pitch brightness noise aswel while i am there

[dwarnecke11]

High-pitched sound = Backlight Inverter Board
Low-pitched buzzing = PSU

Gosh, I'm taking the plung on an i7 in a week, I sure hope it doesn't have these problems :mad:

By the way, which model is it?

[azza2988]

pre-refresh but i pretty much sure seen threads with new refresh i7's with high pitched noise

[dwarnecke11]

So you have a pre-refresh 27" i7?

And post again on this thread after you take it by the store to let us know whats up!

[azza2988]

yep pre refresh 27' i7 i can ignore the high pitch brightness issue but if taking back for some other reason which could cause problems in future may as well get that fixed aswel

[dwarnecke11]

yep pre refresh 27' i7 i can ignore the high pitch brightness issue but if taking back for some other reason which could cause problems in future may as well get that fixed aswel

Yeah, it's still under warranty so go nuts! :D

[azza2988]

been trying to get that noise back cant get it now, have to try again tomoz and kill out films to really get it hot