what is your pc spec? 

well, u dont have to tell windoze version la.
pls tell mobo model number

what is ur main purpose of underclock first? and target clock speed?
win7 can be easily done by change power option.
go advanced, then maximum processor state put eg. 50% or less

i see. i think you can play with cpu multiplier.

hrm. as a multiplayer FPS game player with various computer through the ages - I have no idea how you co-relate processing speed to the ability to hit 100% due to ping or what not.

what makes you think he underclocked?

skill problem cannot be solved by underclocking.

You aren't making sense

Yes games back in the good ol' DOS days/Windows 95 days , there were turbo button. At that upon of time , programmers wrote for machine specific or processor. They just get the processor timing and do rendering based on processor timing (like how long for it to do a fetch-decode-execute instruction) For instance this game would only work on 386 , it would take 1 clockcycle to say to do a shoot action or something , but if you run it on 486 or Pentium 1 , the same set of instruction takes 0.3 clockcycles , meaning things are being speed up.

So the game runs super fast . The Turbo button was there to "underclock" aka force the CPU to run things slower so that it would work with older applications , this way these applications would behave normally as they would on the processor it was written for.

Here is the sad news , you are not living in the late 80s and early 90s and PCs don't have Turbo Button