So this is the PC I am currently looking at (budget of 2000 dollars Canadien)

Antec 900 - 109.95

2 x HD4870 in CF - (50 % off, Family member works for ATI ) - 310.00

Corsair - TX 750 W PSU w/ 140 mm Fan - 114.95

Intel C2Q Q9450 2.66ghz - 359.95

Gigabyte GA-X48-DQ6 w/ DualDDR2 1200, 7.1 Audio, Gigabit Lan, 1394, Dual PCI-E x16 CrossFire - 324.95

Patriot DDR2 4gb (2 x 2gb) - 109.95

SEAGATE- 500gb barracuda hardrive - 84.95

samsung speedplus dvd writer - 27.95

Vista 64 bit

However, I have been told that I should look into 2 gb of ddr3 ram instead of 4gb of ddr2. Any thoughts?

4gb of ddr 2
ddr 3 not needed yet

Stick to the 4GB of DDR2. The difference between DDR2 and DDR3 is insignificant. But you can always benefit from 4 GB

ya tahts what i was leaning towards anyways... but ive been hearing that in the future ddr3 is gonna be quite a bit better. But by that time ill probably need an update anyways right?

Hey dude! That's a good pc u'r looking to build there but I have a few changes that might be better for u....

The Patriot RAM isn't bad at all but rather get Corsair dominator or OCZ REAPER RAM... Go for dominator 5-5-5-15 or OCZ 4-4-4-12. Dominator is worth the higher price and u have a bit to spend so go for it!! Just know that the Mobo u want as well as the DS4 dont like using more than 2 RAM sticks... Well atm people are having problems with it... Hopefully they fix it soon! So get a 2X2gb set of RAM and then u'll be laughing!

Then the mobo u selected is a great mobo, even with the slight issue with RAM both the DQ6 and DS4 are probably the best mobo's out there!! But you can get the DS4 for alot less! I think it's about $60 - $80 cheaper and people are overall happier with them than the DQ6 owners are.... I'm gonna get the DS4 soon... It's basically the same board as the DQ6... Whatever the DQ6 has extra, its not worth the extra $80 and u don't need it LOL

Then just one last comment... U know ur really being a jerk by letting us all know ur gonna get the 2 HD4870's for the price of one...?????
Hahaha u can't maby ship me 2 to South Africa at the same price??

Anyhow have fun with the new rig! it's gonna be fun! Believe me!

Oh yeah... DDR3 is still way too expensive for the little boost it provides... Get some good PC6400 RAM with low latency and OC it or just leave it as it is, it'll do fine... Any RAM above 800Mhz is just factory OC'ed anyway... Check the voltage on them... If it's above 1.8v it's OC'ed.... So no use in buying higher speed RAM

Sorry... Get the Thermaltake ARMOR+ full case too... It's kinda pricey but ur gonna save on the mobo if u follow my advice and its a super case (super in size, weight, beauty and coolong performance)... It's riddled with very large but very quiet fans and has space for a few more! I fell in love with it when i first saw it on newegg, go check it out!!! It's just gonna be a mission to get the damn thing shipped to SA weighing 22Lbs! LOL

Just get it! See this as ur punnishment for bragging with us 2x HD4870's.....

Who ever told you to go with DDR3 wants to steal your money.