2009 iMac 27", video card / GPU problem - worth repairing?

When you boot from it, see if you can find Utilities and if any joy run Repair Disk as I still think this could be a hard drive problem. Let us know the result. If all is okay, erase and format the disk and do a clean install. Then go online and update to OS X.6.8 using the Combo Updater from this link.


https://support.apple.com/kb/DL1399?locale=en_US

Leonard_777 said:

Yes I did do that initially, but it seemed to only give the option of reinstalling the system software rather than operating the OS from the disc itself.
Any suggestions? Must be something I've overlooked.

Click to expand...

That's the way it is. The OS install disk is for installing the OS...and for running some "disk apps"...not for "Operating the OS from the disc". Like Harry mentioned. You can run a couple small apps from the OS install disk (like Disk Utility) for doing various disc checking/formatting/erasing...but that's about it.

If you actually want to "run the OS from a disc"...this is where installing the OS on an external hard drive comes in. The OS install disc is primarily for installing the OS.

- Nick

Thanks Nick.
I'm reinstalling OS X as we speak.

Fingers crossed and 2 time machine backups on separate drives!

Hoping for success!

- Nick

I just completed the reinstall of 10.6 from the original DVD install disk. It starts OK but unfortunately runs very slow and there are some rendering errors on screen (incomplete menus, some blacked out app icons. So it does seem to be vid card / hardware related. Big thanks for your help anyway.

Sorry to hear that no further progress was made. But...the good thing is we can probably say with a high degree of confidence that this is problem is hardware related.

Since this is most likely a hardware issue...and very possibly the video/graphics card...here are some options (other than purchasing a new computer):

1. The graphics card on 2009 27" iMacs is replaceable. So you could try replacing the video card with a replacement used card (found on eBay). Unfortunately even replacement used graphics cards are pretty expensive. And you need to do the repalacement yourself. Otherwise adding labor for someone else to do it can add a lot of cost.
2. If the problem is not the graphics card...then it's probably the logic board. Replacement logic boards are even more expensive than replacement graphics cards. Which on a 2009 27" iMac...the cost of a replacement logic board is usually financially not a good idea.
3. Here's something I've done a number of times with good success when video card issues occur on a 2009 iMac. Replace the thermal paste & thermal pads on the heat sink & GPU. This a very low cost thing to try. For me...the cost of the thermal paste & new thermal pads only cost about $10-$15. BUT...you have to do the work yourself (which is not always something everyone is comfortable with).
4. Since you seem to feel that the repair place you took it to may not be the most trustworthy...you could try a different place...and see what they say.

Hope this helps,

- Nick