Hi nicnac1,
I saw in the screenie above you were overclocking the memory, I was expecting to see approx 533MHz (1:2), Is the FSB 266MHz in that shot or 272MHz
Ok next step, go into BIOS and find the CPU page that shows options like Intel Speedstep, C1E, Execute Disable Bit and disable everything apart from Intel Vanderpool (Virtualisation). Disabling these advanced CPU features is a temporary adjustment while you are doing your basic overclocking tests, at the end of the process we can switch them back on again!
So with all those options disabled boot back into Windows and open CPU-z and confirm that the CPU frequency is fairly static (i.e doesn't jump up and down a few hundred MHz when the CPU is idle), also observe the vCore that is being displayed and make a note of what it is (both when idle and when CPU is loaded), also make a note of what idle and load temps are using Coretemp and Prime Small FFTs test/LinX/IBT
With the chip at stock 2.4GHz (9x266) go into BIOS and change the CPU multi from [x9] to [x6], all voltage settings should be on [auto] at this point, save & exit and boot back into Windows at 1.6GHz (6x266) and run a few tests/games etc for 30mins-1 hour. Your memory should still be running at approx DDR2-1066. What you have done by lowering the CPU multi is obviously reduced the processor frequency but thats not the reason we are doing it, by selecting the [x6] multi you will actually be overclocking your Northbridge Chip from 266MHz to 400MHz, this will be almost the same as actually selecting a 400MHz-FSB which most likely will be stable but 5% chance you may crash n burn!
If that passes fine then back into BIOS, change the CPU multi from [x6] to [x9] and then change the DDR2 frequency from [DDR2-1066] to [Auto] then Save & Exit . . . . .back into BIOS and change your FSB from [266MHz] to [333MHz] then save & exit . . . .back into BIOS again and change the DDR2 frequency from [Auto] to [DDR2-1066] then save & exit and load up Windows.
Once in Windows open up CPU-z and check the CPU is running approx 3GHz (9x333), observe what the vCore is, open Coretemp and then run Prime95 Small FFTs and see what the load temps are like after 15 mins, also observe if the voltage changes much when going from idle/load!
Run a 3.0GHz Quad Core on a 333MHz-FSB/1333MHz System Bus with the Memory at DDR2-1066 through a few games, diagnostics etc and come back when your done!