For people saying that AA1 on board ram is not 667 ant that it's overspeced i've to say it's not true Today i opened my AA1 to look for a way to disable the on board memory (i found one but i have to go to mi University lab to test it, :P). The mem chipset in my mother board is from samsung: and have this noted down in its surface: samsung 831 k4t1g164qq-hce6 gxf2k9eb if we look for this ("k4t1g164qq-hce6") datasheet we found that it's work on 667 Mhz, that it use 1.8v (for people saying using only 1.5v mems) and it's timings: (5-5-5-18) I couldnt find it's power consumption but i've read people saying that using a memory with 2.2w it's ok (it's the power consumption for kingston 555 mhz ram). I've noted so that kingston 1g 800 mhz sodimm ram uses only 1.8W ([URL]http://www.valueram.com/datasheets/KVR800D2S5_1G.pdf[/URL]) less than the 555 mem I'll try tomorrow with an 800 mhz ram module and do some tests butg i'm pretty sure that its mem should be the best option. Remember that u have to take the /1G version (is the one which works at 1.8V). You can also note down the on surface part number of the memory and look for its datasheet on the net. Edit: i forgot saying that the stick module is samsung 512mb 2rx16 pc2 5300 555 12 a3 m470t6554ez3-ce6 0824 samsung 822 It's funny to see the 555 on the label while seeing also pc2 5300 (667) and checking online the stick and chips datasheet confirming it works at 667 mhz k4t51163qe-zce6