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> needs some competition to keep prices in check. Prices as well as the tech itself. $3000 and still just 12GB. I wonder why this isn't in the range of ~64/12

> needs some competition to keep prices in check. Prices as well as the tech itself. $3000 and still just 12GB. I wonder why this isn't in the range of ~64/128GB yet... too expensive for the type of memory?

sliken 9y ago
High bandwidth GDDR5 is more expensive than DDR4. HBM is more expensive again. On top of that the high bandwidth chips are lower density, and the complexity of higher bandwidth links gets more complicated as you get more chips involved. Low end servers use normal dimm, but typically not many dimms per channel, typically 1-3. But to hit the higher memory configurations you end up putting buffer chips on the dimms which makes them more expensive and also slightly higher latency. So 500GB/sec to 128GB ram using HBM2 would be difficult, expensive, and likely wouldn't fit in today's GPU form factors... yet. GPUs generally seem to be mostly hungry for more bandwidth and not that many cases (percentage wise) is 16GB a major limitation. However in those cases check out the power9, the nvlink that x86's uses for GPU<->GPU communication can be used for CPU <-> GPU communication and avoid the high latency/low bandwidth pci-e links.
gbrown_ 9y ago
No-one is manufacturing larger stacks of HBM yet so far as I am aware. If there are it's only a small amount.
andars 9y ago
Larger (higher capacity) HBM2 stacks do not yet exist and the manufacturing process is pretty complicated/expensive. It's worth noting that all the stacks end up on the same piece of silicon as the GPU itself. Don't assume that they are holding back tech due to lack of competition. 650 GB/s is pretty impressive.
krautsourced 9y ago
Even if it just were DDR4 (which of course it is not) - have you looked at RAM prices recently? 128GB will cost you upwards of 1000$ alone. I don't even want to think how much 128gb DDR5 or HBM2 (if it did exist) would cost you... about the current price of the card, probably.

sliken 9y ago

High bandwidth GDDR5 is more expensive than DDR4. HBM is more expensive again. On top of that the high bandwidth chips are lower density, and the complexity of higher bandwidth links gets more complicated as you get more chips involved. Low end servers use normal dimm, but typically not many dimms per channel, typically 1-3. But to hit the higher memory configurations you end up putting buffer chips on the dimms which makes them more expensive and also slightly higher latency. So 500GB/sec to 128GB ram using HBM2 would be difficult, expensive, and likely wouldn't fit in today's GPU form factors... yet. GPUs generally seem to be mostly hungry for more bandwidth and not that many cases (percentage wise) is 16GB a major limitation. However in those cases check out the power9, the nvlink that x86's uses for GPU<->GPU communication can be used for CPU <-> GPU communication and avoid the high latency/low bandwidth pci-e links.

gbrown_ 9y ago

No-one is manufacturing larger stacks of HBM yet so far as I am aware. If there are it's only a small amount.

andars 9y ago

Larger (higher capacity) HBM2 stacks do not yet exist and the manufacturing process is pretty complicated/expensive. It's worth noting that all the stacks end up on the same piece of silicon as the GPU itself. Don't assume that they are holding back tech due to lack of competition. 650 GB/s is pretty impressive.

krautsourced 9y ago

Even if it just were DDR4 (which of course it is not) - have you looked at RAM prices recently? 128GB will cost you upwards of 1000$ alone. I don't even want to think how much 128gb DDR5 or HBM2 (if it did exist) would cost you... about the current price of the card, probably.