RAM question

i’m looking at this ram:
256MB 32x64 PC133 Non-Parity Unbuffered 3.3V SDRAM

what does the 32X64 refer to, and does the voltage make a lot of difference?
also what is unbuffered?

Random web quote :

“32x64 is a description of the chip packages & architecture.”

Re voltage. There are two standard incompatible voltages - 3.3 and 5, IIRC, and I doubt if you can mix’n’match modules with different voltages. Check what voltage your motherboard powers the RAM slots with.

Unbuffered : Quoting again from a web-site - “Some memory module designs (usually those involving large numbers of chips) require a device to re-drive or amplify the signals. On EDO modules this device is called a buffer; on synchronous modules this device is called a register.”
Here’s a top resource for learning more about RAM :