Anyway to answer your question slowly raise the FSB in the bios to overclock.
Most computers will tell you what button to push at startup to enter the bios.
Once in there find the FSB speed and slowly raise it and then save and exit and keep going up until the temps get too high (above 69 is not advisable) or until the computer becomes unstable then go back a few until it is stable and temps are ok and you should be good.
It usually the delete button u press to get into the BIOS from there look for some overclocking options. Mine is MB Intelligent Tweaker. Then Like Protokiller, said Raise the Cpu FSB i think for you its 200 just raise to to 205 then save exit see if its stable then keep going up and if u wish to get your cpu really high in Ghz add voltage.
DONT OC IT! get a fewbucks and buy e4400 or something! it will be hell better than your PD! PD 965 EE oced do 4ghz gives you performance of c2d clocked 2.1ghz! you need to check what cpus does your mb support and take the highest clocked at 800fsb, since your mb wont go much over 800 you need to have high multipler, and keep in mind 45nm are not supported by this chipset. I have mb supported by 945 and i chose e4700, it's G0 so it oc really well, i've got it to 3.46ghz since my mb cant go further, and btw this cpu is cooled by Pentium D stock cooler! trust me, there's no point in ocing that cpu. I used to have PD 920(2.8ghz 4mb cache).
i used to have a PD 940 3.GHZ @ 4.4gHz and its slightly faster than an E4400. if u are on a reallly really really tight budget get a Pentium Dual core E5200 or faster.Its faster than a E4400 and about the same price or cheaper.
Im happy people agreed that the E5200 is the right way to go. Me personally have a Pentium dual core E6300 which was $5 cheaper than E4500 ive overclocked it to 3.6Ghz on a $40 G31 intel chipset gigabyte board and running 4GB Crucial ballistix in 1066mhz dual channel. And thats moving onwards from a Pentium D that ran 30C higher needed loads of overclocking to even catch up to a low end "Core 2" and the architecture is old. oh and Pentium D with HD4830 avoid theres going to be bottleneck in other words Frame Rate Slowdown as the Cpu is not fast enough to keep up with that GPU
I got a Pentium d 2.8 overclocked to 3.35ghz on stock cooler. On a asus p5gc-mx / 1333 MB. It works for general use light gaming. Not the nicest stuff but it has worked for years. Cheap build! Go into the bios and bump up the Front side bus (fsb) to 235. Should be stable unless your heat sink is full of dust or your thermal compound is no good. Make sure your heat sink and CPU fan are clean! This processor runs hot out of the box. My idle temps in speedfan are about 35C idle without the over clocking.45C at full load Runs at about 53 full load overclocked. Max temp for this cpu is said to be 63C
Asus P7P55D PRO Motherboard
4gb 1333 Corsair's Dominator sig series ram
Corsair CWCH50-1 Hydro H50 CPU Liquid Cooler
to put it all in my NZXT Tempest case.
Can't wait! Should be here in about a week, really hope less =)