8200 Elite not booting (only fan does anything)

[retspeej]

This PC was working fine. I put it aside for a few weeks, then switched it on, but little happens. Monitor does not come on,

hard disk no activity, not even a beep code. The only thing that happens is that after about 15 seconds, the fan speeds up.

I would assume that is under control of BIOS, or does it run from independent temperature controller?

I reseated all connectors and changed the CMOS battery, but no go.

So looks like mainboard is dead?It is fairly old (Sandy Bridge).

Unfortunately uses HP non-standard power supply, so I just cannot plug in a spare, like a sensible desktop.

[retspeej · Accepted solution]

I found in some other forums people with the same symptoms. It sounded like a common fault with this model of mainboard.

But it turned out to be a faulty DIMM. This PC should either give a beep code or flash the Num Lock light with bad memory.

It must have been one of those really bad DIMMs that shorts out the memory bus and paralyses the PC.