Ok. You said you used a BIOS from Delidded. Just to rule that out as a possible source of problems try flashing the attached BIOS which I have modified to include latest microcodes for 45mm Xeons. p5kpl-cm-0702mod.zip 625k .zip file
Massive collection. I flashed one of these and encountered no issues.
I also used a bios from there. But several people have used them,and when ck'd they had an older microcode in them. That's why I started the thread for bios that have the newer codes flashed to them (hopefully,we can't make promices for others work) @ least this will give another place to search. Edit: To clarify that a few were found with older microcodes, Doesn't mean all by any means. The 1 I used was fine.
HP ASUS Board IPIEL-LA. bios ver. 513 modded to add 45nm xeon codes and updated rest of 45nm codes from delidded file. USE FILES IN THIS THREAD @ YOUR OWN RISK. NOT RESPONSIBLE FOR ERRORS/BRICKS,ECT. only PROMICE IS NO MALWARE ADDED TO ORIGINAL BIOS FILE.
IPIEL-LA_BIOS_v513moddedxeon.zip 1383k .zip file