Which CPU?

A friend of mine game me an old H.P. computer with windows xp home o.s.
installed.
I found out that the sound was not working and I couldn't get on to the internet.
I thought that the eithernet card was bad and opened up the case.
The is no CPU or heat sink installed,hense my delema.
I asked my friend what kind of CPU was installed,he said pentuim 3.
I've checked online and there a many chips I can use.
The pc only has 128 megs of ram,but that's another story,I would like to go on the low side in replaceing this chip,can anyone give me any ideas of which chip I should purchase?

 

If you can post the model of the pc or the numbers off of the motherboard we might be able to help track it down, cant reccomend any cpu without knowing it will work. ed

 

The model is a H.P.Pavilian 8495,the board is a Tyan computer s1857.

 

Here is the specs on that pc, still cant find out what the mb will accept as an upgrade, keep in mind this mb only supports 384mb of ram. ed

http://h10025.www1.hp.com/ewfrf/wc/...4815&lc=en&cc=us&dlc=en&product=59251&lang=en

 

Thank you!