It will work fine but the processor may not run at 3Ghz, it may run at a slower speed to work with the memory. This will also depend on what options the motherboard gives you. You might try running the memory at a ratio that will allow the processor to run at 3GHz and the memory to run at 333MHz. I would really recommend finding some 400MHz memory which would work the best.
Crucial Performance Lab
The Memory Experts(SM) at Crucial Technology is now on board to give you straight answers to your memory-related questions.
Every board I know of will default PC2700 memory to a CPU:RAM ratio of 5:4 in that configuration. Which means your CPU bus (800 bus has a 200MHz clock and Quad Data Rate) will run faster than your memory bus (160MHz clock, DDR320 rather than 333) and cause a performance loss. But yet it will work, which is your main concern. And in fact it will likely still outperform a 3.06.
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