Before you do anything, if you got a radeon 8500 or a newer non mx geforce or better, that p4 would really fly with one.
well to start off... are you at the point where you have the ability to overclock? I mean can you change the FSB frequency or the CPU multiplier in bios or anywhere else? If so...
you might need a better power supply, there are tons of posts that deal with power supplies and what you need to be able to have to overclock well.
you might want to start in the cpu database that is at overclockers.com to find out what kinda speeds people are getting with thier pentium 4 1.9 ghz processors. you also want go to the forum that is for your brand of motherboard, (intel motherboards) and read all the posts pertaining to your specific motherboard (find out what that is if you don't), and also simular motherboards- possibly simular chipsets or simular speeds.
The more you read the more prepared you will be and will be either more likely to fry something (because you get a wacky idea??!??!) or less likely (because you were prepared??!??!).
In terms of cooling, you should at the very least get some of the good thermal grease, there are some good posts in this section about what types those are.
There are many types of cooling to choose from.
air- worst results, cheapest and least risk
water cooling- intermediate results, affordable, low risk
thermalelectric and other freezing cooling-good results, expensive
The actual risk involved in any of these solutions is mostly determined by how well you know the ins and outs of each cooling solution. If I knew all about thermalelectric cooling and had alot of experience maybe i wouldn't think it was high risk?
I would recommend water or air unless your trying to set 3dmark records- and with the looks of that geforce 2 mx card that doesn't seem likely- but it is a good card... no really I mean it.
if its your first O/C you might want to stick with air- air can be great, you want to maximize the heat conductivity of your heatsinks, and the maximum amount of surface area, and the maximum amount of airflow. you also want to mount your heat sink properly and with some good thermal grease so the heat flows to the heatsink as effectively as possible. Basically the heat sink rests directly on the core of the processor, you want thermal grease to fill in any cracks or scratches or even the smallest of unseen malignant surface features.
But you want your temps as low as possible create a rule for yourself never to run above a certain temperature. A good rule is to take your stock tempurature before adding any special heat sinks or fans and use that as the highest temp you will tolerate- this what I do. And always stay in the green, this is important if you don't want to fry the chip, just make sure you try for reasonable numbers that you are absolutely positive won't fry the chip. Read read read, and when it coems to buy your far more likely to get the right stuff and set it up the right way so that you arn't left out in the cold with a smoking hot CPU.
