Yes, I did that when I found out. Q6600 is a Kentsfield LGA 755 processor with only SSE4. Yorksfield quad's, e.g. Q8xxx, Q9x0x and Q9x5x, are compatible LGA 755 processors with SSE4.1. I would have bought it, but one of my "students" of my "computer maintenance" course seems to want the old PC.