Look at the link in the bottom of my sig. for overclock of OEM computer.
SetFSB was available in freeware and shareware versions. The developer isn't supporting it anymore but the freeware download still works.
SetFSB 2.2.134.98 For me the shortcut doesn't work but the system tray icon does.
Find your PLL chip# enter it, and click GETFSB, if the numbers that come up are correct for your CPU then use the arrows (not the slider) to raise FSB slowly until computer freezes, reboot and raise to lower setting, then click SETFSB. Unless you can raise Voltage results will be small on the CPU side.