Yeah I had compared the 2 CPU's there when doing research on rather or not it was worthwhile to upgrade. I was just a little disappointed when going from the 555 to the 955 but I only did few things for a couple of hours after I switched them out. The windows experience score and the other couple of benchmarks I ran did show an improvement. I think the HDD and possibly the motherboard made the computer feel a little slower than what I'm used to, last few builds I have done have been with Spinpoint F3's or WD blacks and newer mobo's. I'm still just a newb at building PC's that was just my 6th one, still getting a feel for how different components perform when all put together.