
Year in Review 2018: GPUs - egnehots
https://www.anandtech.com/show/13735/anandtech-2018-in-review-gpus
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makomk
Why quad data rate? The fundamental advantage of double data rate is that the
clock signal has the same maximum frequency - and the same signal integriry
requirements - as the data lines, whereas in single data rate it runs at twice
the frequency making it the limiting factor. I can't see much obvious
advantage to going above that though.

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AstralStorm
The quad data rate trick is reading on differentiated and level gated clock.
Actual clock signal is still same rate. Works when clock rates are high as the
transition time gets close to clock pulse time - the clock is no longer
considered square but exponential trapezoid.

It is 2x bandwidth compared to just using clock edges, but requires nice
bypassing to get nice clock transitions and is obviously quite a bit higher
transistor count for stabilization. It is similar to clock doubling but much
simpler and thus faster.

Of course you get some latency benefit.

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blattimwind
Nothing of relevance happened.

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Koshkin
Yeah, still waiting for a ray-tracing quantum-differential-tensor-kanren
GPU...

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frabbit
Are any of these cards supported by FLOSS drivers? If not, then they're
essentially useless for anyone that wants a stable system.

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frabbit
To answer my own question, looks like the mentioned AMD RX580 has a non-Free
EULA: [https://www.amd.com/en/support/gpu-pro-
eula](https://www.amd.com/en/support/gpu-pro-eula)

They can keep it.

