Right now though, I'm reading from quite a few online comments that even with fake frames the higher FPS from the 5090 @4k doesn't feeel like it should in game.
I suspect the poor uplift of 1% minimums/lows is to blame here, in a couple of 5090 reviews it was only around 12% better than a 4090. So plenty more fake FPS from fake frames, but not the in-game experience to match.
That hasn’t been the impression I’ve had at all. TechPowerUp results suggests a 30% uplift on 1% lows across their suite of games at 4k.
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NVIDIA GeForce RTX 5090 Founders Edition Review - The New Flagship
NVIDIA's GeForce RTX 5090 is the fastest graphics card ever released. It comes with a whopping 32 GB VRAM, and support for multi-frame generation, which achieves hundreds of FPS easily. We also managed to disassemble the card, and our review includes performance testing without upscaling or...