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▲ RetroTechie 2 days ago

Bash me all you want, but after CPU, GPU, memory controller & a host of other things integrated in modern System-on-Chips (SoC), I've long held the belief that next logical step would be to integrate RAM.

Optimal: piecemeal. As in: X sockets on a board, each socket takes a chip that adds CPU core(s), GPU cores, and some amount of main RAM. More chips, more powerful computer.

Keyword: socket. Read: replaceable. Bad chip out, good chip in. Slow chip out, faster chip in. Soldered onto board = reliable, but a defect could junk the whole machine.

▲crote an hour ago | parent | next [-]

Considering the current trend is for SoCs to deintegrate: don't count on it.

Putting RAM inside the logic die is crazy expensive - just look at how much footprint L3 cache takes up on a modern chip. It'll always make more sense to put it in a separate die, made using RAM-specific processes. With Zen the memory controller and GPU has (once again) moved to a separate die, and with X3D we're now even seeing separate cache dies.

There's of course HBM if you want to consider that "integrated", but the large cost bump, additional manufacturing risks, and loss of flexibility don't make that an attractive proposition unless you really need the extra speed. Regular DDR dies? You gain basically nothing by co-packaging those.

▲bartvbl 2 hours ago | parent | prev | next [-]

Manufacturing processes for RAM and processor cores are not one and the same and use different tradeoffs. It's the main problem in-memory processing is running into, which is akin to what you're describing here. The die space required for the same level of performance makes the idea of on-die RAM intractible. The best they're able to do with RAM optimised manufacturing processes are tiny RISC-V cores that lack most of the feature sets. What apple does with moving the RAM chips on to the package really is the only viable option.

▲musicale 2 days ago | parent | prev | next [-]

> Bash me all you want, but after CPU, GPU, memory controller & a host of other things integrated in modern System-on-Chips (SoC), I've long held the belief that next logical step would be to integrate RAM

Haven't Apple (A-series, M-series) and others been copackaging memory for a while? (SiP or MCM?)

▲jacquesm 2 hours ago | parent [-]

Those aren't socketed though, are they?

▲xxs an hour ago | parent | prev | next [-]

RAM uses a different process than the logic nodes you describe. RAM uses tons of capacitors, along with the the transistors.

Then there is the HBM which is an expensive process to mount on the chip.

▲vbezhenar 2 hours ago | parent | prev | next [-]

I'm using laptop with Ultra 7 268V. It already has RAM on chip. I think they call it "processor package". I don't think it's socketed, though.

▲skew-aberration an hour ago | parent | prev [-]

RAM on package or on die is common for laptops now.