dude going up 10mhz and testing for EIGHT HOURS is retarded. i dont think i would set it right to 375 tho. maybe a little slower than that, unless you've been that high before(and know how your rig is going to react), which you havent.
i would go to at least 300, test for a couple hours maybe...enough to uncover serious flaws no doubt...then go up another 25 or so. when you start getting it where you want it (or around a known instability point....like for me and my amd that is up around 275-300), then start running longer stability test. there is no reason IMO to test it for 8 hours every 10 mhz. unless you just like running stability tests. lol...hey man, some people do.