If you are doing no overclocking, then get the Platinum Series OCZ, I have heard of problems with the plain EL series. I would go onto Asus' website and find which memory they have tested with the board and which they recommend. I would also look at Mushkin, as their quality is only outmatched by their performance. Have fun!
1) Kingston Hyperx PC3500 CAS2 (if you can find it)
2) Mushkin level1 PC3500
3) Corsair, not sure the model numbers..... but PC3500 CAS would be good
This is for OC'ing or not. The extract speed makes it more stable with more than one dimm in (I assume you are getting a gig)
Edit and I am the one who had problems with OCZ. PC4200 EL to be specific. Only ran at 200 at 2.5-6-6-16.