Looks like I have something workable now. I was under the impression that this counter always ran at a fixed rate, but apparently BIOSs are known to...
How about posting closeup photo's of top left Pins and text on PCB, bottom left pins and text on PCB.
And close up photo of the PADS 0, 1, 2, 3 with...
"Clock error" would usually implicate the COPS chip on the I/O board. That's a tough chip to replace (although not impossible), so my recommendations...