Should I add my other memory?

Hi guy's,

I have 2Gb memory beside me and can't decide if I should add it to my current Rig.

This is what I have:
1 x Intel(R) Core(TM)2 Quad CPU Q8200 @ 2.33GHz
Motherboard Manufacturer: MICRO-STAR INTERNATIONAL CO.,LTD
Motherboard Name: P45 Neo2-FR (MS-7512)
ATI Radeon HD 4850
Chip Type: ATI Radeon Graphics Processor (0x9442)
DAC Type: Internal DAC(400MHz)
Memory: 512MB
Total Physical Memory: 4095MB

2x Memory type DDR2
Module format Regular UDIMM
Manufacturer (ID) Corsair (7F7F9E0000000000)
Size 2048 MBytes
Max bandwidth PC2-6400 (400 MHz)
working at:

EPP profile 1 (full)
Voltage level 2.100 Volts
Address Command Rate 2T
Cycle time 1.875 ns (533.3 MHz)
tCL 5.0 clocks
tRCD 5 clocks (9.25 ns)
tRP 5 clocks (9.25 ns)
tRAS 15 clocks (28.00 ns)
tRC 22 clocks (41.00 ns)
tWR 8 clocks (15.00 ns)


The extra mem I have is Kingston HyperX DDR2
KHX6400D2LL2K/2G 2x 1Gb
Programmable Read latency 3, 4, 5 (clock)
Timing Reference: 667MHz 5-5-5-15 at +1.8V / 800MHz 4-4-4-12 at +2.0V

I know they are a bit slower, but wil 2 more Gb make any difference? I am a flightsim freak , and love every extra frame I get.

2gb will help a lot, I would try it and if you do not like it you can always take them out.

Ok, Will try before I go to RTM build. I like the stability at the moment, will also update bios so I will be updated. So I will have 6Gb in total cool.