Right now, the DC DDR motherboards (P4G8X and 8INXP) are great performing board, the best of what is currently available for the 3.06 w/HT.
If you need to save money, the best 845PE board is the IT7 Max2 Rev2.
With the DC DDR boards you should go with a matched pair of Kinston HyperX PC3000C2 (budget oriented performance w/ better timing at lower FSB) or HyperX PC3500C2 if you plan on serious overclocking. I know that Mushkin black (PCB color) and Corsair platinum work fine too but you will pay premium for corsair and mushkin you might get remarked memory less agressive timing.
Rambus is very fast but DDR beats it in latency, DC DDR can match performance on RDR currently.
350w to 450w should be fine, lean to the higher PSU if you are running RAID drives.
800Mhz FSB parts should be hitting the market in June/July, expect motherboards to be $250+. Im sure we will see a few $300+
Im currently on a SiS655 with DC DDR and HT working correctly. I cannot break 4Ghz with my 3.06 that I know will do 4.14Ghz. DC Memory timing on this board cannot break 400Mhz 2-6-2-2 enhance off @ 170FSB 3.9Ghz
<A HREF="http://service.futuremark.com/compare?2k1=6176517" target="_new">current rig</A> yes Geforce FX 5800 Ultra 580/1120. I wasted no time ripping off the blow dryer and replacing it with a waterblock w/ pelt. The fricken thing was made to operate at 170F without fan active, the copper plate was also on the RAM and would heat the RAM beyond what it normally runs at. the heat plate is a very bad idea, it gets too hot to touch and takes up 2 slots. On this particular motherboard the riser card for the 1394 ports is located in the way.
I can tell that the Granite Bay motherboards I was running are stronger than this one. not by much but I can tell a difference with the games I play and benchmarks I post.
I know this is not a <A HREF="http://service.futuremark.com/compare?2k1=4819419" target="_new">fair compairison,</A> IT7 Max2 R2 also at 169FSB with a slower 2.66C1 @ 3.4Ghz (500Mhz despairity not on DC DDR) with a Radeon 9700Pro.
Yes the R9700Pro so owns the Top end Geforce FX severly overclocked and IQ dumped to the poorest quality.
I used newest drivers, tweaked system, sub zero temps, dumped IQ, single tests @ max Mhz,and yet I still could not break 19K
Even with newest drivers, R9700Pro beats the crap out of the FX in 3DMark2003.
This should be <A HREF="http://service.futuremark.com/compare?2k1=5951448" target="_new">proof enough</A> that Granite bay w/R9700 is the best route currently available for the P4.
Disreguard my cooling methods, I push each as hard as it will possibly go and will test multiple boards to find the best one of each. Do not expect to reach my speeds overclocking I am mearly showing you what they are capable of and performance levels.
<b>"Granted I dont own a P4. But I read enough stuff and waste enough time on forums newsgroups IRC and computer news sites that I proberly know more then if I DID own a P4." -vk2amv</b>