If its still in its black case, look on the top for some numbers, I dont think they even put it on the core on those slot Pen II and IIIs. Like one of mine has a second set of numbers in the first row SL2S7 comes up as a 400mhz
All P2/P3 slot cpus use a "black" case. They heat up too fast though... had a 700MHz at stock speeds freeze cause of an HS only , no fan. Hot glued a fan on and it ws perfect.
yes i mean slot 1 and if you need it i can take or find a picture of one so yall can see what i mean.i want to know the speed with out booting it i have to many to be booting them one after another.