It could be an overheated CPU, so it may be wise to check or replace the
heat-sink thermal paste. It posts so the mobo, CPU & RAM should be OK. One
computer I was working on was thought to have a bad HDD, and the mobo
supported S.M.A.R.T and when I turned that option on in the BIOS and
rebooted it gave me the bad news, like "imminent demise, backup data".
However not all BIOS have that option. Sometimes there are also some
security settings in the bios that can give one a severe headache because
they stop you from booting, but these are mostly in Dells and other brands,
probably uncommon in generics.

Art

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