CPU upgrade boots first time, but then not ...

[Alan Baldwin]

I've installed a Gigadesigns Cube upgrade CPU which I obtained from OWC 
recently.  Installation went fine - booted first time post upgrade.  I 
powered up for the 1st time with the new CPU and the system boots fine 
and runs fine.  If I tell the system to restart (pretty much straight 
away - before any heat issues could occur) the system does not boot (no 
chime, no self test).  If I power-off and press the motherboard reset 
button, then power up and boot, the system boots ok.  But only that one 
time.

So, before every boot, i need to press the motherboard reset button.  
(A little inconvenient!!!)

It's like it will boot if it knows nothing about the system (after a 
system reset), but next time .... ... no go.

Any clues as to what might be going wrong?  Similar problems anyone who 
has upgraded?

Firmware is 4.19f1, btw.

Thanks in advance

Alan

Alan Baldwin