The stock 3000 would be using the faster static rams. The same that cache memory uses.
A 3000 can use static
column RAM, but only with the original '030. '040 or '060 cards won't burst. While it's slightly faster than FPM (theoretically up to 10%) it doesn't make too much of a difference in real life. Just like all main memory types, SC RAM is still dynamic RAM (DRAM).
Cache memory is made up of
static RAM (SRAM) which is an entirely different type - faster, much more expensive and without refresh requirements.
You use DRAM in the megabytes, SRAM in the kilobytes. (External SRAM hasn't been used since the Pentium era in mainstream computing.)
