PleaSe help trying to build a new computer!

[godman]

this is the first time ive built a system before and i was thinking of buying a intel setup, pentium d 805 and overclocking it to something around the 4Ghz mark. i think that this is a good setup but please help/tell me if im wrong
i will be buyin g the parts around august and hoping to upgrade the motherboard, graphics (7900gt) and Cpu (to conroe)at the end of this current year

Intel pentium d 805
£85
http://www.overclockers.co.uk/acatalog/Intel_Dual_Core.html


Corsair XMS2 twinx2gb 800Mhx Dual channel RAM
£160
http://www.overclockers.co.uk/acatalog/Corsair_XMS2_Memory.html

Asus dvd rom black retail
£15
http://www.overclockers.co.uk/acatalog/DVD_ROM_Drives.html

Seagate Barracuda hard drive 160gb Sata2
£45
http://www.overclockers.co.uk/acatalog/Seagate_SATA.html

thermaltake armour jr
£65
http://www.overclockers.co.uk/acatalog/Thermaltake_Cases.html

thermaltake bigwater 745
£70

Thermaltake PurePower 600W psu
£76
http://www.overclockers.co.uk/acatalog/Thermaltake_Power_Supplies.html

any thoughts on a good cheaper (ifyou can get it cheaper) configuration at the same amount of quality and performance as this? also i was thinkingabout a asrock motherboard that will allow me to overclock cheaply
(my original budget was £550 but now ive gone over) i will use an existing x550 from my old comp or i guess i could just buy a really cheap graphics card and keep with that until winter
thanks in advance

 

[godman]

or should i buy a socket am2 that supports the ddr2-800 ram im getting? with a 'cheap' athlon 64 3200+ at around £70 from scan and aslo get a motherboard instad of getting an 805? i would then like to overclock the 3200 but how high an overclock should i expect with the thermaltake biugwater 745? would this be very comparable in terms of performance :
overclocked 805 vs athlon 64 skt am2 overclocked?
thanks