Yeah, normally a RAM or ROM fault. You can tell if ROM is running or not because the diagnostic cartridge should theoretically boot... Or you can use a oscilloscope and checked the ROM chip enables to see if they are switching power up or not...Globox wrote: 17 Sep 2020 18:07 But the top right led (for floppy i think?) not working, and still not working after going back to stock doesn't ring a bell to anyone?
If the ROM chip enables are pulsing several times at power up, then the machine is at least attempting to boot, which generally indicates the machine has a RAM fault... And of course the floppy LED will not blink unless the operating system is running which of course needs working ROM and RAM.

