Bad Display / Graphics Problem with iMac 24" 7300GT
hoping someone can help me with this.
So I assumed the problem was a faulty video card (7300GT) so I bought a new one and fitted it, correctly as I've done this a few times before.
However I'm still getting weird artefacts on the screen, thinking about it they ar different to the ones you get with the GPU overheating/solder problem on these machines, and shouldn't have bought it so quick. anyway..
See the attached screenshots (a combination of red and blue repeating patterns across the screen that redraw whenever you alter the display, i.e. move a window)
So, although not totally ruling out the video card I'm at a loss as to what the problem is.
1.New GPU hasn't helped
2.Artefacts appear on startup (Not software then?)
3.Don't appear to be heat related (SMCfancontrol makes little/no difference)
4. Known working LCD does not alleviate problems
5.Logic board in good superficial condition, I can't see any obvious problems.
6. RAM known working
7. Safe mode makes no difference
So hopefully someone can figure this out?
What I'm leaning towards is
1. Bad new video card?
2. Bad VRAM?
3. Bad GPU daughtercard?
4. Bad Logic board to GPU interface?
5. Bad logic board?
6. Power Issues?
7. LCD cable problem?
Many thanks in advance!