|"CPU: Intel Core 2 Duo E4700"|
Your default CPU clock settings are 13 x 200MHz frequency @ 800MHz FSB.
"RAM: 1x2GB DDR2 400 MHz, 2x1 GB DDR2 400 MHz"
My guess is you have DDR2-800 RAM which runs at 400MHz frequency.
"MB: GIGABYTE P35-DS3L"
Your board officially supports up to 1333MHz FSB (333MHz frequency).
I deliberately bolded all the frequencies to show you that they're all different. For best performance, they should all be the same. Since the board officially supports up to 333MHz frequency, that's what you should shoot for. I suggest you drop the CPU multiplier from 13 to 9, increase the CPU frequency to 333MHz, & configure the RAM to run as DDR2-667. That will put the CPU at 3.0GHz @ 1333MHz FSB with the RAM running in sync at 1:1 ratio.