Dumb RAM question

[mubs]

I shouldn't be asking this, but I'm still stuck in the Pentium-3 era, so forgive me.

Will a stick of PC-2100 work in a system that needs PC-133? AFAIK, they're the same, speeds and all, just old wine in a new bottle, so it should work.

TIA!

 

[CityK]

No.

SDR SDRAM uses 168 pins
DDR SDRAM uses 184 pins
(DDR2 SDRAM) uses 240 pins

 

[Buck]

In addition to the pin count being different as CityK outlined, they are notched differently, theoretically making it impossible to use the RAM.

 

[mubs]

Thank you, CityK and Buck.