"CPU fail" light on 1.1 running x5355

I have recently pimped my 1.1 with x5355 CPUs. After a few months it started doing its own restart when waking from sleep. Hasn't been a big deal until today my wife forced it to sleep, and left it sleeping for the day. It now won't boot up. Machine starts, disks whir, but no chime, no screen start-up. tried unplugging and leaving for 30 mins. Same thing.

There are four lights on the motherboard that say CPU Fail (b,a) and CPU overtemp (b,a). The first two (for Fail) are lit.

Should I just stop stuffing around and put the old processors back in, or is there a solution?

Thanks.

Bugger!

(I hope that "Australian-ism" translates ok )

I have an Apple 5770 graphics card, and an SSD running off the SATA port on the motherboard. SSD has OS, 2x1TB RAID for home folder, all other drives and peripherals removed.

Thanks for replies.

Well, I put the old 5160 CPUs in... No good. Same problem.

Logic board? = new machine doesn't it?! I can't imagine a logic board would be good economics in this machine.

Any last minute ideas?

Thanks

Fixed!!!

This is in case anyone else is having the same problem in the future:

I found a list of Troubleshoots for the problem.

No 4 on the list was: Removing the battery off the motherboard for 10 seconds. Fixed it (so far)!

I noticed after the restart that only 10 GB of 12GB RAM was showing. I checked the risers and there was a red light on the lower one (with two 1GB DIMMs) so I took them out and shuffled the remaining ones around. Might have been the cause?

Thanks to all for your help