iMac trouble (black screen after upgrade)

[keltbrat]

So, i picked up 2, 2010 iMac 21.5's for next to nothing. Figured i would upgrade RAM and put an SSD in each.

Upgrading one went smoothly, but the other i'm having trouble with and wondering if anyone can help.

I went through the usual procedure of detaching all 4 cables to remove screen but when re- attaching again i damaged the display port cable. i bought a new replacement display port cable and put the iMac back together, but now when i turn on , i get the chime, it turns on, but screen stays black. Any ideas or help very much appreciated. Thank you.

 

[Juicy Box]

You could connect the iMac to an external display, or use the working Mac as an external display in Target Display Mode, just to rule out potential non-display related issues.

You could also swap displayed between the Macs to try and rule out stuff.

 

[mikehalloran]

Replace the NV RAM battery. Black screen is a symptom although probably not the cause here, it’s old enough to be the cause. Since it’s on the back of the motherboard of a 2010, you’ll have to reexamine all your connections and cables.

If you reset the NV RAM and it flickers or comes on, you have a weak battery. The original is a heat resistant BR2032. A CR2032 works fine since you’ve removed the heat pump that was the HDD.

If you put any pressure on the GPU, you probably stressed a solder joint. Baking the GPU fixes this. Plenty of threads.

It can be the LCD backlight or power to it. Plenty of threads on that, too.

 

[aman88]

So, i picked up 2, 2010 iMac 21.5's for next to nothing. Figured i would upgrade RAM and put an SSD in each.

Upgrading one went smoothly, but the other i'm having trouble with and wondering if anyone can help.

I went through the usual procedure of detaching all 4 cables to remove screen but when re- attaching again i damaged the display port cable. i bought a new replacement display port cable and put the iMac back together, but now when i turn on , i get the chime, it turns on, but screen stays black. Any ideas or help very much appreciated. Thank you.

I did the same upgrades to my 2010 iMac and the same thing happened so I opened it up and realized the display cable (which is a pain) was not attached. So I attached it, closed it up, and it’s worker great since....

I should say I didn’t damage the cable I just didn’t get it connected correctly...