This is a good article on techradar "Wait for AMD to make its Big Navi move before you buy the Nvidia RTX 3080"
 
It has been a while to see AMD being competitive with Nvidia in the graphics card market, so you can either wait for them to each show their cards before buying, or just stick with one if you can't wait.  

I would wait, but IMHO their drivers are trash. So for me, it doesn't matter how good their hardware is if their software isn't. I know a lot of people say they never had a problem, but I'm talking from personal experience, always problems, same for my friends that all have AMD, never again. Their CPU's are good now, but I don't think they have the resources allocated for their Radeon tech group (be it personnel for R&D, drivers etc).

vegajf51

jamexr
I would wait, but IMHO their drivers are trash. So for me, it doesn't matter how good their hardware is if their software isn't. I know a lot of people say they never had a problem, but I'm talking from personal experience, always problems, same for my friends that all have AMD, never again. Their CPU's are good now, but I don't think they have the resources allocated for their Radeon tech group (be it personnel for R&D, drivers etc).

You don't wait for Big Navi to actually buy big Navi, you wait because Nvidia will respond with price cuts/Super models. 3080 Super 20GB for example is just waiting to be released.....

Which is actually sad, for AMD. I wish they would really compete for the top end with Nvidia, it is good for all us consumers... Welp, at least they are doing so with Intel now...

wmunn
The thing to keep in mind here, back before 2017 AMD really was struggling from behind for a multitude of reasons.
New management came in, and laid out a plan to success. They are hitting on all cylinders and steadily progressing every year. Now attention has shifted to the radeon group, so I would expect the improvements in Radeon to continue. I fully expect them to give Nvidia a run for their money starting this year, but really becoming apparent on the following product cycle.

I would really be surprised if AMD gives NVIDIA a run for their money this year. Going from the 2080Ti to the 3080 we saw the biggest leap in performance that we have ever seen while the cards also had a huge price drop. Last time AMD tried to keep up with just the 2080 and they couldn't really keep up with that. Now they have to race against a card that is offering 30% more performance then a 2080Ti that now is the same price as a 2080 last generation. If they pull that off it would be the biggest generation leap any graphics company has seen in performance in two decades.
 
I think that above is why NVIDIA might not have any current plans for a 20GB card or a Super or Ti. I feel that it will be an arrow that they will save for if they need to refresh in a year or possibly longer. It's just hard to see AMD having gone into development thinking that NVIDIA would aim the flagship card at a $699 price point and I am guessing they thought it would be $999 or more.

Well you are going to be "waiting" either way....     Combine the current unknown waiting list for Step-Up with the fact that it hasn't started yet.  We don't know what percentage of cards will go to Step-Up or when even.  So that process is going to take a while....
 
If there is a card you actually want and would use then buying something now for Step-Up could work I guess.  As for "Big Navi"..   Well beyond the performance possibilities good or bad.  I would expect pretty much the same outcome as current Nvidia cards when it launches.  Lot's of them showing up on Ebay with sites crashing etc when they come into stock.

That reason would be RTX 20 series didn't sell nearly as well as 10 series, and for good reason. not enough jump in performance.