If your spare psu is verified working (not just turning on by itself by jumping pins w paper clip, but powering on another motherboard to POST in a different pc), then consider replacing 7010 MB.  used MB inexpensive on eBay [URL]
This unit sat for a couple of years. I now need it. I had to replace the CMOS battery. When plugged in to power, LED does not light. When I press the diagnostic button, LED lights up solid green, so no physical problems. What to do?
7010 no start