Dell Optiplex 980 boot problem

[airplanepilot501]

I have a Dell optiplex 980, I’m getting three errors,
‘Drive 2 not found: Serial ATA, SATA-2’
‘Alert! Memory population error for DIMM 4’
‘Alert! Failed to detect one or more of the faces during POST.’
‘System halted’

 

[william p]

I've had malware that did that. 3 different errors. There are a few things I do to approach a problem like this. Load a Linux Live DVD and see if it will run from a DVD drive with the HDD/SSD unplugged. Replace MB battery and reset BIOS defaults. If this runs then your hardware is working.
If not then I would look for swollen or leaking capcitors on the MB. That's getting to be old enough it may have that problem.
Malwarebytes Anti Rootkit is a free scanner and catches things Antivirus don't. It can't always fix them though.
Then an Antivirus, and then a Malware scanner.