…Is it that interchangeable?
TBH I know little of memory fabs, but I know (say) TSMC and their customers can’t just switch from a power-optimized process to a high frequency one at the drop of a hat.
…Is it that interchangeable?
TBH I know little of memory fabs, but I know (say) TSMC and their customers can’t just switch from a power-optimized process to a high frequency one at the drop of a hat.
tty5@lemmy.world 3 days ago
Slightly different part, same process. The bigger bottleneck is packaging - HBM is 3d stacked.
brucethemoose@lemmy.world 3 days ago
Ah. Yeah. And its on the fab to do that.
I always though it’d be cool for CPUs to switch to packaged RAM, too. Samsung apparently tried to do it with Wide I/O for mobile ARM stuff, but it never caught on.
frezik@lemmy.blahaj.zone 3 days ago
If I’m following what you mean by packaged RAM, Apple does that. It’s fast, but you can’t upgrade it.
brucethemoose@lemmy.world 3 days ago
That’s (as I understand it) a misconception.
Apple attaches their laptop RAM the same way all smartphones do. It’s a wide bus with LPDDR, which makes it an unusual configuration amongst laptops, but it’s technically conventional.
AMD’s Strix Halo chips are the same.
When we talk ‘packaging’, we’re talking putting chips on advanced substrates with denser wires than one could possibly get on a motherboard (or a ‘mini’ motherboard which is kinda what Apple/smartphone RAM is packaged on), stuff silicon fabs have to do:
www.tsmc.com/english/…/advanced-packaging
And HBM falls into this bucket. The way its hooked up to the CPU is physically different than PC RAM sticks, or Apple’s RAM.