Good information bro.

I dont have a 939 rig but something I have seen with mine is that going to one stick gets me no-where higher in MemTest... BUT different Drive Strength values work better depending on how many sticks I am running.

See if setting your Drive Strength from Weak to Normal makes a difference with 1 module Conrad... I have more choices here cos I am with a DFI but I found a weaker value for 1 stick sometimes helps, whereas for two modules Drive Strength 4 is the best for me.