What FPS will I get in Red Dead Redemption 2 at 1440p?

At 1440p Ultra native, expect around 180 FPS. With DLSS Quality you can push higher.

Does GeForce RTX 4090 Phantom GS support DLSS or FSR in Red Dead Redemption 2?

Yes — Red Dead Redemption 2 supports dlss2.

Yes — the GeForce RTX 4090 Phantom GS runs Red Dead Redemption 2 at approximately 240 FPS at 1080p Ultra (native, no upscaling).

✓Yes — Excellent

Expected: 240 FPS @ 1080p Ultra (native).