Does it boot with another 512 MB 3200 400 MHz ram installed or two 1GB 2700 333 MHz ram, (if you are able to test)?
It looks to be 1) the motherboard is having issues with the two different RAM's because they are either have different timings, voltage requirments or both. Typically, you have issues with mixing ram when these two are different. They try to run at the slower speed, which the 400 MHz might have issues at the 333 MHz settings or 2) Your motherboard isn't truly capable support 1GB sticks per DIMM slot. I see it can support up to 2GB but I only see one 1GB QVL... http://www.asrock.com/mb/memory/P4i65G.pdf