Update: Make that 5 920s tested. Just got another from BuyNow.com. Looked at the sticker, another week 41 chip, version#002, a bad sign. Sure enough, a dud. This one runs cool, but can do only 3927Mhz in my standard prime run of Vcore=1.344 HT off, Tuniq Tower 120 at 2100 RPM. My 'good' chip has done 4116 Mhz with identical settings and components. My two good chips are both week 37, version #001. Are the later chips generally weaker, or is this just a coincidence?