thanks would it be worth it to invest more money for the 6800 or wait to see what this fidelity fx is like ?
That's something only you can determine - I can't pick it for you.
The purpose of DLSS is more performance at the cost of image quality. The AI takes things - like shadows and edges - that players are less likely to notice during game play, and scales them down.
Basically, use it in titles where performance takes a dive. With the 3070, both RT and DLSS can be run together; they pretty much cover each other's backs... but that only applies in supported titles.
I'm looking at the RX 6800XT - RTX 3080, with favor towards the former:
-I don't care for RT in its current state; the performance hit is still too much, IMO.
-DLSS can offset that hit, but none of the games I currently play even support that feature anyway. A whole lot of good that does me...
-Even if I did play games that support it(RT), I see myself trying it out once or twice, and not bothering with it again. It's just not there yet with rasterization.
But alas, my favor for the RX 6800XT is dashed by AMD suffering from even worse supply woes than Nvidia. I have better odds of getting a 3080...
Well, it's not too terrible, since those 2 cards are very close in performance - that's not the case for you, as the RX 6800 does have a nice edge up over the 3070, as far as rasterization goes, at least.