G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 (PC2 8500) Price: $189.99 Sale Price: $144.99
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231166

Here's a comment from newegg:

Rating + 5Rating + 5Rating + 5Rating + 5Rating + 5 Excellent stuff, worth the premium
Pros: Why worry if your memory is holding back your overclock? Get these and have no worries.
Cons: For the price, would have liked these to be certified 4-4-4, but no big deal as not much else is...
Other Thoughts: Have 4 x2 GB of this running in my Win Vista Ultimate 64-bit machine on a Gigabyte GA-X48-DQ6 mobo. It's silky smooth (set DDR volts to +0.3)

I'm assuming you will overclock, otherwise you could save money and get some cheaper MB and DDR2-800.