The problem is that the CPGA Durons (and TBirds, possibly) have the
multiplier set in TWO places: The L6, which tells the M/B what multiplier to
use, and the L1/L2/L3/L4 setup which tell the CPU what to use. Some BIOSes
check to make sure these are equal, and won't POST if they are different.

Sorry, but you are slightly in error here. L1 controls unlocking. L3
and L4 determine multipliers. L6 determines Muliplier ID. These
bridges do work the same way on Thunderbird.

I only learned recently how imortant Multiplier ID for Spitfire Duron
(a 600). Although mine was factory unlocked (L1 bridges not cut) and
I had it working with BIOS multipliers (9.5 x 106 Mhz= 1007 Mhz) I ran
into problems when performing wire mods (wire-in-socket in my case).
I used the same mods that I was using for a TBred B XP1700+. Set it
for a conservative 7X x 133Mhz. No joy. Realizing I had never tested
the Duron on this motherboard (EPoX 8KTA3PRO, KT133A) I decided to
retest at 100 Mhz. Only the default 6X would work! Tried 7X, and 9X
(perhaps a few others). Still nothing. I confirmed everything I tried
with my Tbred yet the Duron refused to POST.

Going back to BIOS multipliers the Duron worked perfectly. In fact
with a much better HSF than I had while the Duron was on my Abit KT7 I
am able to overclock it to 1112 Mhz (8 x 139). This is with the same
board on which I was trying the wiremods.

I gave up.

A month or so later I was re-reading John C's website and also
OCinside.de when it dawned on me that the functionality of the L6
bridges exists on the pin grid. With Tbreds and unlocked Bartons we
need only perform wirmods on pins AN27, AL27, AN25, AL25, and, AJ27
for multipliers (0.5X...8X) but on Spitfire/Thunderbird (and I think
Palomino) we need also mod'd pins W1, W3, Y1 and Y3, Multiplier ID
pins. At least it's necessary with legacy motherboards (all I have).
Anyway, once I learned this there were no more problems with the
Spitfire.

Phsstpok