Its a oem without HS but its 478 pin with 2.8 speed and it costs 20$ less than the 2.4. With the D0 stepping all prescotts are based on the starting speed wont bother you much as the ending speed is usually the same. Get a decent heatsink to use on this. Also the Celeron D's I have worked with show a linear increase in cpu benchmark as the speed increases i.e.(pcmark04 or prime95) a 50 percent increase in speed gave me a 51 percent increase in cpu benchmarks. But to let you know any celeron d you get is only three fourths as powerful as its base speed suggests so a 3.6 will yield the benchmarks of a 2.8 P4 on the other hand its a budget overclocker and if you fry it you can replace it cheaply. I use them because I love to overclock and see how I can push them.