Black screen on iMac 27" late 2009

[vliz]

I have a late 2009 27" iMac with blue vertical lines. I opened it and tried to bake the video card and put it back in but I got a blank screen with the backlight on. I connected my iMac to TV to see if the video card is toast but it showed up okay on my TV screen. I bought a display port cable thinking I broke it and installed it, but it's still showing black screen. Anyone has any idea or suggestion what I should do? Maybe I broke the vertical sync cable?

 

[bbasra]

LVDS Cable?

 

[vliz]

I ordered a used one from powerbookmedic.com but it still won't work. I wonder if it's a bad cable or I broke another cable?

 

[Daveyoasis]

I have been having similar problems.this what happens after leaving my late 2015 mac to sleep every time without fail. Is it a hardware of software problem? It is the same since upgrading to Sierra.

Apple care have told me to take it back to the shop.

I am going to be sneaky and take it back when the new macs are out and insist on a swap for a new one. Wonder if this will work? After spending £1700 on a computer I expect it to work perfectly.

 

[havokalien]

How about the connector to the motherboard? its a known weak point, if you pulled the screen too far out before removing the cable you may have seperated some of the connections.

Also the video card may be an issue. 2008-2011 imacs graphics cards start failing pretty regularly.

 

[KALI609]

Hey trying to revive this thread. Any update from the OP? Was it your video card or something else?