I have a second iMac 4K 2019 that I attempted to upgrade the RAM, NVMe, and HDD. This is the i5-8500 model. I disassembled it and installed the upgraded NVMe 500GB, 32GB of RAM, and 1TB SSD drive. After performing the upgrade, I turned it on.
Sadly I got the black screen of death, no chime, or anything.
I decided then to try to do one upgrade at a time, starting with putting back the original 256GB NVMe and removing the 1TB SSD drive. Again, same results. At this point, I put back the original 8GB of RAM - in essence back to its original setting - same result, no chime or display.
I'm at a loss as to what could've happened. If you peak in into the logic board with the display carefully attached to see the LED diagnostics lights, here's the sequence of events:
1. Plug power cord in
2. LED1 lights up first, then LED2 lights up momentarily
3. Fan begins to rev but iMac turns itself off
4. LED1 stays on, then LED2 lights up again and stay on this time around
5. Fan begins to rev up
6. Ultimately, the display does not come on
Does anyone know what else to try? I've tried resetting the NVRAM by holding the following keys the same time: ⌘ + option + P + R, but I don't get a chime, either during bootup or attempting to reset the NVRAM.
Any advice would be awesome!
TIA....JP
Sadly I got the black screen of death, no chime, or anything.
I decided then to try to do one upgrade at a time, starting with putting back the original 256GB NVMe and removing the 1TB SSD drive. Again, same results. At this point, I put back the original 8GB of RAM - in essence back to its original setting - same result, no chime or display.
I'm at a loss as to what could've happened. If you peak in into the logic board with the display carefully attached to see the LED diagnostics lights, here's the sequence of events:
1. Plug power cord in
2. LED1 lights up first, then LED2 lights up momentarily
3. Fan begins to rev but iMac turns itself off
4. LED1 stays on, then LED2 lights up again and stay on this time around
5. Fan begins to rev up
6. Ultimately, the display does not come on
Does anyone know what else to try? I've tried resetting the NVRAM by holding the following keys the same time: ⌘ + option + P + R, but I don't get a chime, either during bootup or attempting to reset the NVRAM.
Any advice would be awesome!
TIA....JP