Expreview has compared Intel's upcoming 45nm Core 2 Duo E8400 based on the Wolfdale core to a Core 2 Duo E6850, as both CPU's are clocked at 3GHz. The improvements of the new core include larger cache and SSE4 support, but apart from that there aren't any major differences between the two chips.
Expreview managed to overclock the E8400 to 4.05GHz and it was stable at this speed with a normal air cooler. The comparison at 3GHz compared to the E6850 shows that the Wolfdale core is on average about one to five percent, but can be as much as over 10 percent faster. They've also compared the performance in Half-Life 2 Episode two, with the CPU at various speeds from 2.33 to 3GHz.
The impressive part is power consumption, where the new core uses almost 20W less under load. It also runs about eight degrees Celsius cooler at idle and 11 degrees cooler under load.
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