Hi, I have an ASUS-P5RD1-V mobo that I purchased in March. I assembled all the components and installed 256 mb of memory. It has windows-xp-sp2. It was working fine until recently. I installed another 256 mb of ram (same type and speed). Still working fine until recently when at startup, the machine would get stuck at mobo logo and would not go any further. I turn machine off and then back on, it works ok. sometimes i have to do this 2 or 3 times. and when it keeps going, at P.O.S.T., sometimes it says: overclocking failed, press f1 to go to setup. press f2 to continue with defaults. after f2, it loads windows and all is well. sometimes, the mobo log is distorted and fuzzy, sometimes it's ok. i also got a msg once: cmos check sum bad. I have tried the memory sticks indivitually they seem to be ok. i even installed a single 512 mb new chip, same problem. I have tested cmos battery and it shows 3.2 volts. any ideas what could be causing this? thanks much.