Alright, since you said you have an Intel CPU then you are uping your FSB. The multiplier is locked on Intel P4 chips (at least on the 533FSB chips), so the only thing you can do is raise the FSB.
So, you said that you went from 2.8 to 3.3GHz.
If you have a 533 FSB (actually 133 "quad pumped"), that means you have a multiplier of 21. That is locked that only thing that you can change is the FSB so, changing 133 to 157 will bump you up from 2.8 to 3.3GHz and that is a big bump.
Soyo Dragon Ultra Platinum Edition powered by a P4 3.06GHz w/HT @ 533FSB
ATI Radeon X800Pro 256DDR <---Yeah!!! I finally got it!!!
1024MB PC3200, Creative Audigy LS, 2 x 40GB = 80GB RAID 0
Windows XP Pro, DOOM 3, CS, UT2004, BF1942 RtoR, CNC Generals
Finished Half-Life 2!!!!!!!!!!