Hi...I have had the bios freeze issue with 0706 and bios 1003, however a reboot and re-entering the biosnormally corrects this...regards

Trefi should be changed via the dram timings menu, yes you could use the amd overclocking menu, keep things simple use the dram menu to configure your dram, what bios version are you on...? 

Hi.....Glad you got sorted, enjoy your system

Have you tried with only 1 dimm ?