iMac 21 will not boot after CPU change
I bought a Intel Quad-Core i7 875K CPU to replace the 3.2Ghz i3 in my 21" iMac 2010. This is specifically the same as the Intel 870K in the guide here on ifixit. I followed the guide and was careful to assemble everything back, all cables and screws.
Now the iMac will not boot. The fans go on but there is no chime and no picture on the screen. Is there anything that could cause this? When I look at the LCD message lights on the logic board, Light 1 and 2 are on only.
I now tried to put back the i3 CPU and the iMac behaves exactly the same. I wonder if I have damaged the LVDS cable that connects to the logic board. Could this be the reason it does not start and only turns on the fans?
I would appreciate any thoughts about this. Maybe someone experienced the same.
The iMac is booting just fine now. I bought a new LVDS cable. The connector on the logic board seems fine to me. But there is no picture on the internal LCD and when I connect an external monitor I see no internal LCD in the displays in system configuration, only the external monitor. I would avoid buying something that is not broken but I have no other LCD to test with. Does it seem the logic board can be damaged? Should I try to change the GPU?
The LED lights on the logic are lit, 1-2-3 , but not 4.