I am working on a computer that was self built and was working fine until one day the owner tried to boot that computer.
When the computer is turned on sometimes the monitors won't work but the computer seems to boot as I have to hold the power button for several seconds to get the computer to shut down.
Other time, this is most of the time, when the computer gets past the BIOS screen a black screen with: "Invalid system disk Replace the disk, and then press any key" appears. There is no disk in the ROM. The HD is a 750 GB WD and checks fine. I have checked the RAM with no errors. If I tap any key several times it will finishing booting sometimes and sometimes it won't
When the computer boots it works fine. Any suggestions. Thanks.