Originally posted by Thunderbird1GHz
sram, isnt that essentally offdie cache?
That’s one of the uses for it, but almost al cache is SRAM whether it is on the die or off.. SRAM is memory made from logic gates or transistors. (usually 4 or 6 transistors per bit) while DRAM is memory made by storing a charge on a capacitor and only requires a single transistor.

DRAM is denser, meaning you can pack more of onto a chip. SRAM is faster and can be made using the same production process as a microprocessor, which means you can easily put it on the processor die.

There is also something called eDRAM which stands for embedded DRAM. It’s basically DRAM integrated on the chip just like SRAM is. The problem with eDRAM is that its more expensive to make a chip of a given size, the clock rate of the chip is a little lower, and its still not as fast as SRAM. On the upside you can get about 5 times as much of it on a chip, so you could put a lot more cache on a processor.