For MSM:
Most of the processors made in the last 18 years fall under the last two categories:
$5.50 Green Fiber with Heatsink - Pins
$4.25 Green Fiber with Heatsink - Pinless
Processors made prior to year 2000 often fall into these categories:
$13.25 Green/Brown Fiber without Heatsink
$13.25 Slot Processor
( That's the simple answer )
A little more complicated: Look at how the processor is made. Answer the following questions.
1: Does it have a cap ? ( heatsink )
2: Does it have pins ?
3: Is it ceramic or fiber ?
4: If fiber ... what color is the fiber ? ( Green,Brown,or Black.)
=======================================
Bottom line: My guess would be that it's a P-4 made sometime in the early to mid 2000's but more information is needed.
Could you post a pic -or- list the information imprinted on the heatsink ?
That would help narrow it down for Ewasted. :)