We have a PRIMERGY TX200 S2 that yesterday was running absolutely fine. As it is the end of term, the students at my place of work are currently off, and so we take this opportunity to perform maintenance on our servers (such as Windows Updates etc). I ran a set of Windows Updates on the TX200 and once they had finished I rebooted it. Since then it has not worked, it fails to boot up, nothing shows on the monitor display and I get a POST error beep code in the sequence 1-3-3-1. I've checked everything, all the SCSI cables, all the PCI cards, I've seated the DIMMs in 2A+2B, 1A+1B and 0A+0B and none of them cause the system to boot up, I just have the same problem every time. The RAM has not been upgraded/changed from it's original configuration at all, it just is failing the POST all of a sudden.
I've tried a basic boot up with all expansion cards, optical drives and HDDs removed, and even running with just the one CPU, but nothing seems to fix it. Is it likely to be a dead MB?