Imac 20" - Is my graphics card gone?

Hello everyone!

My Early 2008 iMac 20" (2,66ghz, 4Gb, 320HD, ATI HD 2006 Pro 256mb) is not booting up for some days now.
I get all the usual startup sounds, the Apple logo, rotating wheel and all. When the desktop backgrond picture was supposed to come up, it doesn't, the screen goes white and I get the Apple logo again.

I've tried every sugestion i've found online, but the only way to boot is in safe mode and this way it runs fine, with the safe mode limitations, of course.

Yesterday I've read somewhere that this can happen when the graphics card is failing and that I could try deleting (I've moved to another folder) every file beginning with ATI in /system/library/extensions.

I've done that and my iMac boots up again but with very low video performance (1650x1050 resolution but almost no video playback and some of flickering when displying photos and redrawing web pages).

My question is: Can I be sure I have a fried up graphics card and get a new one?

Thanks!

Nuno

I don't know that your graphics card is actually the problem, but the answer to your question is no, you can't change out the graphics card in an iMac. I'd suggest you have a trained Apple-approved tech have a look at it.

That really does not sound like the graphics card but I could be wrong. Can you in safe mode make a new user account then log into that and see if the issue is still there?

Otherwise I agree with Chas. Get it looked at by Apple if you can.

Thanks guys!

I've even formated my Macintosh HD and re-installed Mountain Lion and the issue remains.
@Chas_m: I was basing the possibility of replacing the graphics card on this: iMac Intel 20" EMC 2133 and 2210 Video Card Replacement - iFixit

Nuno

Ah, ok, if you totally reinstalled that sounds more like a hardware issue. I have that almost identical Mac and had no issues with it at all. Now running Mavericks with not an issue.

There was one or two models that had a plug in graphics board. I know for sure mine is not one of them. Mine is an ATI HD 2600.

Interesting, I just read that iFixit article and it looks like maybe my iMac has that card and it it hidden by all the heat sinks and metal in there. What is the exact ATI Video Card in your iMac?

I just checked the EMC 2133 and that is my machine! Interesting. I have been in there 5 times now and never noticed it with all the covering and metalwork. VERY interesting to know this. Thanks for that URL. Unless you start to take out the Logicboard you would never see it.

I just wonder where you would get the card as it's made for that iMac.

It's an ATI Radeon HD 2600 Pro - 256mb

dtravis7 said:

I just wonder where you would get the card as it's made for that iMac.

Click to expand...

Found one on German Ebay, not too cheap though...

http://www.ebay.de/itm/Grafikkarte-...er_Sonstige&hash=item338840ef93#ht_2131wt_998

I found the Logic Board on US Ebay but without the video card. Will keep looking.

That price does seem up there as this logicboard was no where near that price.

Thanks Dennis!

Here is one. It's still pricy but new they are many hundred dollars!

A1224 iMac 20" ATI Radeon HD 2600 Pro 256 MB Video Graphics Board w Heat Sink | eBay

And another.

http://www.ebay.com/itm/APPLE-20-A1...0-PRO-256MB-Graphics-Card-Board-/271314647545

I'd look here too (to compare):
replacement Mac video cards for all Apple desktop & laptop computers

(make sure you know if it's NEW or refurb)

Tough as it sounds best suggestion may be to sell the iMac as parts on eBay and such and look for a later model, 2010/2011 at least.