iMac won't boot, no chime, black screen
So I had a mid 2007 iMac with 2.0Ghz core 2 Duo CPU, and it was really slow, so I upgraded the RAM, CPU, Wlan card, and also to an SSD around 70 bucks.
It performed really well in MacOS Catalina, and I realized, that I did not plug in the mic’s cable into the motherboard. Went back, took apart the whole machine again, and assembled just as a new. Now it won’t boot. I can’t hear the startup chime, and the lcd is also off. The first 3 diagnostic leds always turn on when the machine starts.
I’ve already tried SMC reset, PRAM reset (bluetooth, usb keyboards not working), switching ram modules (it won’t beep if it doesn’t have any), also tried the old HDD, issue still remains. I had even tought about baking the logic board and GPU, but I don’t think any of them are faulty just bc of a reassembly. Do you know how can I fix that?
Ist dies eine gute Frage?