Recommended memory upgrade

[Mercury]

Abit IP35 / 2GB - recommended upgrade?

I have an Abit IP35 with Intel Core 2 DUO E6600 "LGA775 Conroe" 2.40GHz (1066FSB) CPU and Corsair 2GB DDR2 XMS2-6400C4 TwinX (2x1GB).

I'm currently running Windows XP but want to re-install using Vista Ultimate 64-bit (which I already own), so I would like to upgrade to at least 4GB RAM.

What would you recommend I do (for the least amount of money)? Would I be able to buy something like this to replace my existing memory? Would it be compatible, or should I be considering trying to order another 2 x 1GB identical Corsair modules?

Thanks for any advice!

 

[KingZeddy]

Some will say upgrade, I would say if its cheaper to add more of the existing ram then do that, the difference in performance in little

 

[C64]

What I would do is buy a 2x 2gb set and sell on your current ram.
Running 4 x 1 gb sticks on an Ip 35 will require a bump in northbridge voltage but that's about it.
For overall stability less heat and better clocking I think it's regarded 2 sticks is better than 4.
Having said that it's perfectly fine to run 4x1gb sticks have done so my self without any issues on vista 64 and ip35pro.
But I'd rather have 2 sticks than 4.