oscillator problem

[Acetronics2]

The only thing to watch when overclocking is that things like serial comms ad the like often wont work. I had an 18F4580 running on a 20Mhz xtal with the HS_PLL setting - whilst it wasn't probably running at 80Mhz, it was dammed fast - but non of my serial comms would work until I replaced the 20Mhz xtal with a 12Mhz one. (as spotted by Alain)

I was going to suggest that you tried using the xtal from the breadboard that you know was a proven crystal... but now you seem to of resolved the problem. - I have to agree with Alain, I would only purchase from a large component retailer (RS in my case).

Hi, Malc

your problem was setting correctly the OSC related registers ... not a Xtal problem ...
as you were running @ ... 4x 12 Mhz !!!

for PBP ... it is not overclocking, as those frequencies are in the compiler's list ...

@ Kamikaze

looks there's a supply stability or glitches problem that doesn't allow the PLL to stabilize quickly ... add a 10/22 µF Tantalum bead as close as possible to the PIC !!!

You also can poll for the PLL stability flag before allowing your program to run ... ( for execution sake )

Alain