Elixer
Lifer
- May 7, 2002
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The basic design still should be the same, it is highly doubtful they found something that they would have to change completely after silicon has been made.The question that I don't know the answer to is, if AMD had to do a significant change to the layout of the silicon in order to remove some kind of show stopping problem, could that require significant rework of the drivers that they already had. The silicon that they had might have been nowhere near what they were expecting and needed, so they had no choice but to delay Vega and fix the problem and take the hit on the delay.
Though, come to think of it, it is possible there is indeed a hardware bug, and they are trying to work around it via drivers. That wouldn't be unheard of.
If we look back to the TLB bug on Phenom CPUs, that could cause a whopping 70% decrease in performance trying to fix that via software (BIOS).
That required a new stepping to fix without that massive performance hit.
Now, for that to be the case here, it takes ~16 weeks for a major respin, ~8 weeks for something minor. Then add a few weeks for the fab to stop & start again.
I can't seem to find the revision of the chip that is being used for Vega FE on any of the sites that bought the card, anyone know?
Anyway, it could very well be possible that they actually have a new Vega revision for RX,
the TLB I mentioned above, AMD stopped the fab orders in Nov. 2007, and it wasn't until April 2008 before the fixed version was out and shipping.
That would mean that AMD would have had to have a new version of Vega ready by Feb 2017 before we would see inventory at the end of July.
Yes, this scenario is far-fetched, in that, they would have to be shipping bugged Vega FE cards, and the specific workload only shows its ugly head on things that don't have to do with the more "professional" benchmarks that we have seen.
Can't disagree, this is one oddball release.If that's not what happened, then I've got nothing else at the moment to explain this confusing morass of a release.