if you're unstable at 4ghz, then back off. 4ghz is just a nice number, but there is no rule that says you must be running 4ghz. also, there is nobody on the forums who can use your computer and figure out if you are running 3.8ghz or 4ghz without opening cpu-z. you simply cannot tell the difference as it is too small of a difference. my point is: don't run borderline unstable just so you can say you're clocked at 4ghz. rather, shave off 100 or even 200mhz and run your computer at 3.9 or 3.8 and be 247 stable. it's that simple.