Should i use 800ddr2 or 1066ddr2 for phenom 9400

[jluis2xp]

i mean i do get more band with with the 1066 which means more preformance but i'm als looking for system stability. with whichone will i get an overall balance between preformance and stability. the processor has a maximum of 3.6ghz of hyper transport fbs but motherboards are only running it at 2.6 maximum


motherboard-
GIGABYTE GA-MA770-DS3 AM2+/AM2 AMD 770

link
http://www.newegg.com/Product/Product.aspx?Item=N82E16813128081

processor- AMD Phenom 9500 Agena 2.2GHz 4 x 512KB L2 Cache 2MB L3 Cache Socket AM2+ 95W Quad-Core

link- http://www.newegg.com/Product/Product.aspx?Item=N82E16819103226

Memory- Kingston 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 1066
OR
G.SKILL 2GB 240-Pin DDR2 SDRAM DDR2 800

Links

http://www.newegg.com/Product/Product.aspx?Item=N82E16820231121
http://www.newegg.com/Product/Product.aspx?Item=N82E16820134586