iMac 2009 27" - Why the fuzz???

[bbbowers]

My old computer finally died and now that I got a new one I figured I may try to revive it to use as a kids/school computer (just basic apps). However, I don't want to dump a bunch into it. Does anyone have any ideas on what could be wrong with it? I think it may be the graphics card or the HD but disc utilities shows everything is fine.

Specs
27" Late 2009
2.66 Ghz i5
12 gb 1067 ddr3
ATI radon HD 4850 512 mg
OS X El Capitan 10.11.6

Problem: When going to startup disc it will only go to this fuzzy background, gets very hot and just does nothing but fuzz. It also makes a sad start up sound like a "haunted iMac startup" lol.

What I did: I did erase HD, reset ram, reinstall new OS X El Capitan, run utilities, run safe mode, and I did get it to install OS X El Capitan... Then moved computer to new location I turned it on again and back to the same thing. Just a fuzz background. I can get it to go to utilities (command r) just fine and that works but it will not load past that fuzz.

So, my question before I get a new hd package from owc, is his something that sounds like an HD problem? Or is this something more pricey like a new graphics card, or more.

 

[tyc0746]

Not sure what you're meaning by "does nothing but fuzz", and 'fuzzy background' as the pictures look fine.

But, the easiest way to check if the HD is dead/dying would be to install MacOS on an external USB-connected HD and try to boot from that. If it works then it's probably the internal HD.

It may still be the graphics card, but there's not a lot you can do with that without opening up the machine - and if you're going to do that, you might as well install a small SSD in there at the same time to give it a new lease of life.

 

[bbbowers]

Hmm, maybe you are seeing wrong photo. The photo that it goes to after everything is the fuzzy background that is blank... It will not load the OS.

Okay, I will try and do that and see what happens.

 

[Fishrrman]

This sounds like something "on the motherboard" -- CPU or GPU related.

It probably -could- be fixed (motherboard or GPU replacement).
The question is: how much do you really want to spend on it...?

 

[bbbowers]

Not more than 100-200. I can get a used 2011 as a kids computer for not much more than that.

 

[rpmurray]

What kind of environment were you running this in? If it hasn't been opened since purchase then the fans may be clogged with dust. This model has the glass held on with magnets so it's relatively easy to take it off. The difficult part would be removing the LCD so you can get at the fans.

You might want to read the Apple Technician Guide to see if you want to give it a go.

 

[bbbowers]

It has been used as our daily computer for since we got it 10 years ago. It has lived a nice long life. It has been opened once a long time ago after apple techs tried to fix the screen. We had candles near it (very dumb and lesson learned) and it pulled in the smoke which settled on the inside of the screen. This was probably 8 years ago.

Alright, maybe I will try that. I am not having any luck making a bootable usb. It must not be the HD.

 

[zoom25]

Hi, I also have a Late 2009 27" iMac w/ 12GB RAM and Core 2 Duo processor. When I reinstalled the OS to High Sierra, I remember at one point it was stuck at the fuzzy screen and other screens for quite a bit. I thought something was broken, but the OS just took a long, long time to boot.

Have you tried leaving the iMac on for a few hours straight? I left mine on overnight and it was fixed by next morning/afternoon.

 

[bbbowers]

Here is the current status. I tried reinstalling osx several times. Left it going. Got it to boot but it was all fuzzy icons and glitchy. Now it only goes to this when I turn it on. Photos are when I wake it up, and then once I enter a random password (must be a default one?) To log in.
[automerge]1589147536[/automerge]
Here is when I try to open settings. To clarify I have tried reinstalling osx several times and this is what it has done each time. So does this seem like a graphics card issue?

 

[DeltaMac]

Looks like a failing graphics card.
Your main symptom is the screen shot that shows the big blue box (first attachment in your post above)
The tiny dots all over the menubar is typical of failed graphics.
All the software reinstalls aren't going to help that. If you want the good fix, you have to replace the graphics card.

 

[bbbowers]

That's what I was afraid of. Not as cheap as just getting a new HD lol. I may just junk it unless I can find something reasonable.