Intel Core 2 Extreme QX9650, formerly known as Yorkfield, is the first 45-nm desktop CPU from Intel, being a quad-core CPU running internally at 3 GHz and externally at 1,333 MHz, the same clock specs of Core 2 Extreme QX6850. QX9650, however, brings two novelties: the new SSE4 instruction set and a larger 12 MB L2 memory cache, making it the most high-end desktop CPU available today. Did these two new features improve the CPU performance? That is exactly we are going to find out.