Sometimes, a little, and it depends entirely on which kind of suppression you run and which part of your PC is already under strain. No universal number exists, because the answer on a high-end desktop in a CPU-bound esports title has almost nothing in common with the answer on a mid-range laptop in a demanding open-world game. The good news is that measuring it yourself takes about half an hour and requires only free tools.
Where the processing actually happens
Noise suppression is computation, and computation has to run somewhere. There are two places it can land.
CPU-based suppression includes the filters built into OBS and the noise suppression inside Discord. The lightweight, traditional methods use so little processor time that they are effectively invisible. The machine-learning methods cost more, though on a modern multi-core processor the load is still small, because audio is a tiny amount of data compared with video. Where it can matter is on an older or low-core-count CPU that is already saturated by the game plus a software video encoder. With no slack left, even a modest extra task can show up as stutter.
GPU-based suppression means NVIDIA Broadcast, which runs on RTX-class cards. It keeps the CPU free, which sounds ideal for gaming, but the GPU is usually the component a game leans on hardest. If your graphics card is already running flat out, the audio model competes with rendering for the same silicon.
So the useful question is not “does suppression cost frames” but “which component has headroom on my machine?”
Setting up a fair test
Frame rates wander by more than the effect you are trying to detect, so a fair test needs a repeatable scene, a consistent method and more than one run.
Pick the most demanding game you actually stream, since that is where headroom is tightest. Find a segment you can repeat closely: a built-in benchmark is ideal, and a replay, a training map route or a fixed drive through the same stretch of a level works too.
Use a monitoring overlay or frame-capture tool that logs results instead of just showing a live counter. You want the average frame rate and also the one percent lows, which describe the worst moments and correlate with the stutter you can feel. Log GPU and CPU utilization alongside.
Test under real conditions. If you stream, have OBS open and encoding, to a local recording if you prefer not to go live, because the encoder is part of the load your system carries. Let the machine warm up for a few minutes first, so thermal behavior is the same across runs.
Run the comparison
Do three runs with suppression off and record the numbers. Then enable your suppression of choice, confirm it is actually processing by speaking into the mic, and do three more runs of the same segment. Change nothing else between the two sets: same graphics settings, same resolution, same background programs.
If you are choosing between options, repeat the process for each one. Try the lighter method in OBS, the machine-learning method, and GPU-based removal if your card supports it. For a sense of how these tools are typically configured before you test them, the streamer-focused guides at loadoutaudio.com cover each one, and starting from a sane configuration keeps your comparison meaningful.
Averaging three runs per condition smooths out the normal variation. If the run-to-run spread within one condition is as large as the gap between conditions, the honest conclusion is that there is no measurable difference on your system.
Reading the results
A change in average frame rate that falls within your normal variation can be ignored. Pay closer attention to the one percent lows. A suppression method that leaves the average untouched but drags the lows down will make the game feel worse than the headline number suggests.
Look at utilization too. If the GPU sat at its limit during the baseline and the GPU-based effect lowered your frames, you have found your bottleneck, and a CPU-based method is probably the better fit. If the CPU was the saturated part, the reverse applies. If both had room to spare, use whichever sounds best and stop worrying.
Should you find a real cost, there are ways to reduce it without giving up clean audio. Lowering the strength of a GPU effect reduces its load. Capping your frame rate slightly below the maximum leaves the graphics card a margin. Switching video encoding to the dedicated hardware encoder on your card frees up CPU time.
Measure once, then stop wondering
Forum threads will argue about this forever, because everyone in them owns a different machine. Your own six benchmark runs settle it for the only setup that matters. Repeat the test after a major hardware or driver change, and get back to playing.
