I'm building a triple-monitor sim racing setup and want to maintain roughly 75 FPS with high graphics settings. I mainly play Assetto Corsa with Custom Shaders Patch and post-processing filters, but I also occasionally play other simulators such as iRacing. My three monitors are 27-inch 1440p 120 Hz displays, so the combined resolution is 7680×1440.
I initially considered using DLSS 5, but I'm removing that from the requirements after realizing how demanding it currently is. I also stream through OBS and would use GPU-based encoding when appropriate.
My current system includes a B550 AM4 motherboard, Ryzen 7 5700X3D, 32 GB of DDR4 memory, and an RTX 3080 Ti Founders Edition. The 3080 Ti currently averages around 45 FPS in Assetto Corsa with the settings I want, or roughly 60 FPS after compromises, which still feels too choppy. I'm trying to determine whether the main limitation is GPU performance, the 12 GB of VRAM, or something else.
I'd prefer to keep the rest of the system for now. An RTX 4090 is difficult to find and slightly beyond my budget, while an RTX 5090 is completely out of reach. The RTX 5070 Ti and RTX 5080 are more realistic options, and both have 16 GB of VRAM. Would either be a worthwhile upgrade for triple 1440p sim racing and streaming, or should I be considering another card?
3 Answers
The key issue is the pixel count: triple 1440p is 7680×1440, which is a huge rendering workload. A 16 GB card should be more comfortable than the 3080 Ti, but VRAM capacity alone won’t guarantee 75 FPS. You’ll also need to check GPU utilization, VRAM usage, CPU frametime, and whether particular CSP effects are causing the slowdown. Between the cards you listed, the RTX 5080 is the more sensible target if it fits your budget; the 5070 Ti may work, but it leaves less performance headroom for demanding tracks, weather, traffic, and heavy shader settings.
Don’t overlook AMD options if your streaming setup and game compatibility are covered. A high-end Radeon card can offer strong raster performance and plenty of VRAM for triple-monitor gaming, though Nvidia may still be preferable if you rely on its encoder, specific simulator features, or better support for your chosen upscaling tools. Whichever card you buy, verify the actual bottleneck first and consider reducing the most expensive CSP effects rather than lowering every setting globally.
GPU encoding generally has a small impact on gaming performance, so OBS itself probably isn’t the reason you’re stuck around 45 FPS. It’s still worth checking the stream preview and encoder statistics for dropped frames.
Your Ryzen 7 5700X3D is still a strong choice for sim racing, especially since the X3D cache helps in many simulator titles. Moving to a new DDR5 platform would add cost without necessarily fixing this particular problem. The 3080 Ti’s 12 GB can become restrictive with high-resolution triples and heavily modded Assetto Corsa, but the larger concern is that the card is simply rendering 11 million pixels every frame. A 16 GB RTX 5080 would be a reasonable upgrade while keeping the rest of your hardware.
I’d first test with the same scene while watching GPU usage and frametimes. If the GPU is pinned near 100%, lowering CPU-related settings won’t help much; if it isn’t, a CSP effect or CPU limitation may be responsible.