Ill just buy it day one as 3080 will be faster than 4 year old titan pascal. This card got tooo many hours in itSo how do you get those performance figures? You read independent review websites.
Reading companies own figures won't give you any real information - Nvidia used HDR to make Turing look much more performant than it was over Pascal and AMD marketing had the Fury X matching a GTX980TI.
If Nvidia and AMD released no performance figures would anyone pre-order a GPU?? I doubt it.
This is what all these performance previews do - build hype for pre-orders/first day orders which usually appear before reviews.
I play 4K and missing some juice for constant 60fps ans 2080it was not worth the money for performance jump for me and still on old node.
I would though, recommend seeing reviews and weighing up the pros and cons before buying one of these new gpus. They might actually be as good as Nvidia says they are, BUT, there might be a few caveats with them, great performance only in certain game titles, tend to run a bit on the hot, prone to space invaders like the 2080ti was I believe, the 3070ti with 16gb Vram might drop earlier than expected possibly due to AMD punting a gpu that was/is better than expected at a reasonable price point, plus loads of other caveats that i can't think of.
