Ok I just worked out from reading a few threads on the net concerning the P5Q. Basically you can't set a specific ratio, its done automatically when you choose which RAM speed you want to run at. It will give you options that aren't always like 533, 667, 800, 1066, so you will have options such as 700Mhz for a 1:1 ratio if the FSB is 350Mhz and you will have several other options which will equate to ratio's like 2:3, 4:5 etc.
Basically if you set your RAM speed to 800Mhz while the FSB is 266Mhz, the ratio will be around 3:5 (FSB:RAM) or something. So basically if you change your FSB, the RAM speed will increase according to that ratio hence why you had the higher RAM speeds I believe.
So the easiest thing to do is simply change the RAM to the 1:1 ratio at the time and leave it at that.
I might be wrong about this, but this is how I have interpreted. Good to see its stable at 1hr. Anyway if you have any problems just change the RAM to 704Mhz (I think I read your using 352Mhz FSB), otherwise if its stable keep it as it is.
I am quite surprised, a semi-coherent post I think lol.