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Non-binary DDR5 memory could be a game-changer for businesses everywhere

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Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#21
post #9

Here I was, hoping for ternary RAM: 1/0/-1. Didn't Burroughs field a ternary machine, once?

Ternary is fun but hard to integrate with existing systems. The headline made me think about storing two bits per cell, like MLC flash does, with 4 levels of charge instead if 2.

Can’t you use ternary internally but exposed binary to the system?

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#23
I was imagining something like super fast analog not-quite-precise storage for things that don't need a huge number of IEEE-754 bits, like maybe graphics cards. I bet there are lots of applications for fast FPUs that don't care about a few LSBs.

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#25
post #21
post #9

Earlier quoted context omitted.

Ternary is fun but hard to integrate with existing systems. The headline made me think about storing two bits per cell, like MLC flash does, with 4 levels of charge instead if 2.

Can’t you use ternary internally but exposed binary to the system?

That's what PAM-4 signaling does. Quaternary signals can be easily broken up to binary ones on the other end because the bits divide cleanly. For the same reason why hexadecimal encodes binary very well.

Signalling systems that don't divide cleanly into a number of bits are more complicated to work with; you need to group bits together into another group of terts[0] and assign states to each. It's less like "picking the bits between the bits out" and more like MFM/GCR encoding for magnetic media.

[0] Ternary digits. No clue what the official name is for these but I am not going to go with the obvious choice.

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#26
post #9

Here I was, hoping for ternary RAM: 1/0/-1. Didn't Burroughs field a ternary machine, once?

Ternary is fun but hard to integrate with existing systems. The headline made me think about storing two bits per cell, like MLC flash does, with 4 levels of charge instead if 2.

Same.

Alas, sensing the contents of a DRAM cell in the time allotted is already a tough ask. Having to discriminate between multiple voltage levels would surely make have a nasty latency impact.

OTOH, I believe DRAM senses entire rows at a time -- so after that latency hit, bandwidth might be unchanged.

Any idea if it is even possible with existing capacitive DRAM cells?

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#27
post #4

This is a short article about allowing RAM sizes that aren't powers of 2, like 24 GB or 48 GB instead of just the steps 8 GB, 16 GB, 32 GB. I initially thought this was going to be about using multiple states on the data pins to encode more bits per clock.

I thought it was going to be about non-binary RAM: RAM cells that store information in one of 3+ states.

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#28
post #16

This is the least exciting news I’ve read in my life.

Right. Just what we needed, more product differentiation in RAM. Like Intel's 22 versions of the same basic CPU. 10% faster! 2x cache! ...

24GB and 48GB DIMMs are useful, and that's what this is about-- allowing non-power-of-2 sizes (in this case, 3x a power-of-2 is now allowed).

This has the potential to noticeably reduce costs in many cases.

Re: Non-binary DDR5 memory could be a game-changer for businesses everywhere

#30
post #28
post #16

Earlier quoted context omitted.

Right. Just what we needed, more product differentiation in RAM. Like Intel's 22 versions of the same basic CPU. 10% faster! 2x cache! ...

24GB and 48GB DIMMs are useful, and that's what this is about-- allowing non-power-of-2 sizes (in this case, 3x a power-of-2 is now allowed). This has the potential to noticeably reduce costs in many cases.

Well yeah but it's not interesting. It's like saying there's a whole new kind of tire - that is 13.5" wide unlike the 13" tires we're used to. Useful? Yes. interesting? No.
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