Alternatively referred to as the PGA370, the Socket 370 is a processor socket first introduced in November 1998 and the first used with the Intel Celeron and the Pentium III Coppermine. The original Socket 370 has a 66 MHz FSB (front-side bus) and 2V core voltage. As seen in the picture, the socket has 370 pin holes and has a small lever on the left side of the socket that can be pulled up and pushed down to insert and remove the processor.
The first revision of the Socket 370 looks identical to the original version, but is internally different. The updated version of the Socket 370 has a 100 and 133 MHz FSB and a core voltage from 1.5 V to 1.8 V.
When Intel introduced the Tualatin Pentium III processor, it revised the Socket 370 socket again. Like the previous revision it looked visibly the same, but the processors that worked with the first revision were incompatible with the new socket. This last revision has a 100 and 133 MHz FSB and core voltages 1.45V and 1.5V.
Below is a basic overview on how to install a processor into a Socket 370 socket.