What FPS will I get in Slay the Spire at 1440p?

At 1440p Ultra native, expect around 0 FPS. With DLSS Quality you can push higher.

Does GeForce RTX 4090 Phantom GS support DLSS or FSR in Slay the Spire?

Yes — Slay the Spire supports dlss2.

Yes — the GeForce RTX 4090 Phantom GS runs Slay the Spire at approximately 0 FPS at 1080p Ultra (native, no upscaling).

✕No — Too Weak

Expected: 0 FPS @ 1080p Ultra (native).