first set your pci-x to 100, turn off all auto controls for cpu
remember to check your cpu temps in the bios and physically feel the memory and nb. You need to add a 40mm fan to nb if you are over 1200fsb, if your system crashes in heavy gaming and nb is hot add this fan mod. The 40mm fan will screw into the aluminum slots with 3/4" sheet metal screws.
Set your fsb to 1500 375x9 = for 3.4ghz you may have to settle for a little as 1200fsb. set your cpu voltage to 1.45 (1.4 to 1.5max) - you can lower it later 1.38-1.42v
if you can not boot into 1500-1400 fsb try lowing your multiplier to 8
set your ddr speed below its rating - i.e. ddr 800 set it 720 or so
set your latencys and your ram voltage. set one at a time if you have 4-4-4-12 ddr 800, if it locks up try 4-4-5-12, set the 1 or 2 last or leave it at auto
set your ram freq to its normal setting and voltage - if it works set the voltage higher try to oc the ram. must ram runs at 2.1v good ram runs at 2.2.v over 2.3v you may have problems with ram degrading as with the 680i chipset.
set your nb/memory contoller if you use fsb 1500 use the second or third setting- i think its 1.55v. p5b-e likes auto setting so set it last.
you should end up with
4-4-4-12-1 Vmem= 2.1-2.2v or 4-4-4-12-auto
2.8-3.4ghz with mutliplier of 8 or 9 with fsb of 1400-1500
Vcore = 1.42 or so
you want a fast clean boot into windows after you get it tuned - if you system is haning up or crashing loading windows - your memory is too fast or too low of voltage in almost all cases.
I built and shipped 3, 3.4ghz systems last 2 weeks with e6600's and these settings! The e4300 has the potential to run the same speed with its 9x multiplier. The bottom is antec 900 and the top NXZT! Note: the memory cooler and 40mm fan on the p5n-e.
Also note both systems run with a stock intel cooler! no need for any expensive cooler at 3.4ghz.
iHint: if you get hung up at certain cpu speed try a lower multiplier and and higher fsb see which has a lower temp in the bios that is the right multiplier in many cases!
2nd - remember to load windows ad default settings and if you crash its the memory!