I wanted to test and see if I could unlock the two extra cores in my Phenom II with my BIOS... Didn't go so well. Computer wouldn't POST or display anything on my monitor. So I unplugged everything and reset CMOS using the jumper on my motherboard. I then turned it back on and hit DEL, and before it went to BIOS, I noticed that it recognized my RAM as DDR2-800, instead of DDR2-1066. I figured the problem will solve itself after I hit "Load Optimized Defaults" or whatnot. So I loaded the optimized defaults, and exited the BIOS... ...and nothing's changed. My RAM still only shows up as DDR2-800 instead of DDR2-1066. It's unganged as it always was. I didn't do anything to the RAM. CPU-Z reports exactly what BIOS reports. Is it possible that I screwed it up when I manipulated the cores and such?
It's fine, it's just defaulted to the SPD settings. RAM is a dumb animal entirely controlled by the motherboard - you have to manually set it to 1066 for it to run at 1066. The sticker on the side is its "capability" but is limited by the other hardware: CPU, BIOS, motherboard, cooling. Memory will ALWAYS reset to the native defaults of 800 for DDR2 and 1333 for DDR3 to make sure your PC boots. Doesn't that Gigabyte board allow you to unlock one core at a time? You could have a triple core CPU work, maybe?
Something else to add to this, if you were overclocking before the ram will have been ramped up accordingly. My board runs natively @ 800mhz but because of the overclock it's now ticking along quite happily way beyond 1066
