memory question

[Modcon]

I have just bought myself 2 sticks of gigabyte corsair twinx ram i aready have 1 gigabyte of corsair twinx in two 512 megabyte sticks in my motherboard. should i upgrade it to 3 gigabyte or should i just use the 2 gigabyte in dual channel,
If you see what i mean will it be overkill going to 3 gigabyte or not?
(I mainly use my pc for gaming and the internet and photowork.)

 

[Modcon]

Jetway 939GT Sli G - Motherboard
AMD Athlon 64 X2 Dual Core 4800+ (Socket 939) - Retail (ADA4800CDBOX) (CP-129-AM) - CPU
2 x Corsair 512MB DDR XMS3200C2PT Platinum CAS2 (MY-007-CS) - Ram
2 x Seagate Barracuda 7200.9 80GB ST3808110AS SATA-II 8MB Cache - OEM (HD-051-SE)

 

[Modcon]

Thanks for the help i will do that