No startup after CPU and SSD replacement, diagnostic LED confusion
2017 iMac 27 Retina 5K, i5 3.8, 8GB VRAM EMC 3070
I just swapped my CPU to the 7700K and changed out the SSD to a Feather Turbo 1GB. The Feather is supposedly loaded with High Sierra and listed to be compatible. The HDD is wiped and formatted. Expected to boot into a restore or have to restore from USB.
Followed the documented procedures and everything seemed to go well. Go to power up and nothing happens. Pull off the glass and find the diagnostic LEDs. There are FIVE.
Plugged in, there is definitely power. LED 1 lights up green and steady.
When I push the power button though, LED 1 just blinks as long as I am holding it down. When I release, LED 1 is steady. Nothing happens beyond that when I push the power button. I removed and checked the powder supply to ensure all connections were secure; they were and the problem persists.
I have looked around a ton now and cannot seem to find any reference to a blinking or flashing LED 1 when the power button is depressed. LED 2 does not come on at any time.
I can find the basics on the LED meanings for the main FOUR but this is not covered and nothing seems to be said about the fifth one.
Any ideas? Does this sound like a PSU or Logic Board issue here?
Tore it back down and in the process of reattaching the heat sink and that insanely overbowed tension spring, I had accidentally unseated the CPU.
Unfortunately, this also seemed to bend a single pin in the socket. With some phone magnification and a needle, I managed to get it back in what appears to be a reasonable orientation and think it might be OK.
I won’t be able to test as in the process of removing the heatsink, the processor delidded (I bought it used, previous owner had already delidded and added liquid metal, but it appears the reseal was weak), SO, now I have to wait for a rocket 88, and some Grizzly Cryonaut and Conductonaut to arrive Monday to repair the delidded CPU before I can put things back together and see if that socket pin is OK.
Pretty likely that this is why I never got the 2nd LED to light. At least I hope so…CPU was almost certainly unseated….definitely cockeyed when I opened it up and was careful to note that....will have to see once I get the parts sorted.
Update #2 (09/20/2019)
Re-lidded the processor (Used Conductonaut, for now I am not going to concern myself on the long term implications of that).
Reassembled everything and was very cautious to maintain the alignment of the CPU in the socket. I also managed to realign the bent pin to a point where it appears to be nearly indistinguishable from the surrounding pins, so hopefully we are going to be ok there.
After reassembly, I now get diagnostic LED 2 to illuminate, but no further. Fan starts spinning and you can hear the HDD spin-up and the head moving. There are no chimes and there is nothing on the screen.
The Feather SSD is supposedly loaded with High SIerra so it should boot. It did not. I tried booting into recovery mode, safe mode and off of a USB with the Mojave installer and it will not recognize anything. I installed Mojave’s in full on the HDD and tried that, nothing.
Keyboard does not seem to connect, no power on caps lock light even when connected by cable, maybe Inhibiting recovery boot cmd?