Here is what I know for sure- On intel's website under Core i5 470UM is says it can handle up to 8GB. The HP TM2 has the same processor and it's logic board has two slots and can handle 8GB. The 8GB ram modules that you can buy right now are rated at 1333mhz and the EP121 is rated at having 1066mhz for RAM. So I did a bit of research on it and found that 1333mhz ram module can replace 1066mhz modules. The worst thing that can happen is that it will only use 1066mhz of the 8GB module and since they are ECC they will not cause the computer to crash.I think that is not that bad if that is the worst that can happen. I just want to know if anyone has installed one yet.