CPU and GPU Usage Both Low While Gaming? Here's Why (and How to Fix It)

You open Task Manager while your game stutters at 45 FPS, and you see something baffling: your CPU is at 35% and your GPU is at 40%. Neither component is anywhere close to maxed out. So where is the bottleneck? Why is your expensive hardware just... sitting there?

This is one of the most common and most confusing performance problems in PC gaming. A traditional bottleneck is easy to understand — one component is at 100% and everything else is waiting. But when nothing is at 100% and performance is still bad, it feels like your PC is broken.

It's not. There's always a reason, and in our scan database, we see this pattern in roughly 1 out of every 5 systems that report poor performance. Here are the seven most common causes, ordered by how often we see them, with a fix for each.

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1. A Single CPU Thread Is Maxed Out (the Most Common Cause)

Task Manager's overall CPU percentage is misleading. When it says "35% CPU usage," that's an average across all cores and threads. If you have a 16-thread processor and one thread is pinned at 100%, Task Manager reports 6.25% — even though that one thread is the hard ceiling on your frame rate.

Most game engines have a main thread that handles the game loop: physics, AI, game logic, and draw-call submission. That thread cannot be split across cores. If it maxes out, your frame rate is capped by that single thread's speed regardless of how many other cores sit idle.

How to confirm: Open Task Manager, go to the Performance tab, right-click the CPU graph, and select "Change graph to → Logical processors." Look for one or two cores pinned at 95–100% while the rest idle. Or use MSI Afterburner's overlay with per-core CPU monitoring enabled — you'll see the bottleneck thread immediately.

How to fix it:

• Raise your game's resolution or visual settings. This shifts work from the CPU to the GPU, effectively slowing the GPU to match the CPU's pace. Your FPS stays similar, but image quality improves for free. This is the same logic behind fixing a traditional CPU bottleneck.
• Enable DLSS, FSR, or XeSS at a higher quality preset rather than lowering resolution — these upscalers keep image quality high while letting the GPU fill its idle time.
• Close background apps that compete for the same CPU thread. Browsers and overlays (Discord, Steam overlay) add draw calls that land on the main thread.
• If your CPU has P-cores and E-cores (Intel 12th gen+), make sure your game is pinned to P-cores. Windows' thread scheduler usually handles this, but you can verify in Task Manager by right-clicking the game process → Set Affinity and ensuring P-cores are selected.

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2. You're Hitting a Frame Rate Cap You Forgot About

This one catches more people than you'd expect. If your game is capped at 60 FPS and your hardware can push 180 FPS, neither the CPU nor GPU needs to work hard to hit that target. Both will sit at low utilization because they're being artificially held back.

Where frame rate caps hide:

• In-game FPS limiter — check the game's video settings for a max FPS or frame rate limit option.
• VSync — locks your frame rate to your monitor's refresh rate (usually 60 Hz). If you have a 60 Hz monitor and VSync on, both CPU and GPU will throttle down once 60 FPS is reached.
• NVIDIA Control Panel / AMD Adrenalin — global or per-game frame rate limits set in your driver software.
• RTSS (RivaTuner Statistics Server) — if you use MSI Afterburner, RTSS may have a framerate cap set.
• Monitor refresh rate set wrong — a 144 Hz monitor running at 60 Hz in Windows display settings. Right-click desktop → Display settings → Advanced display → check the refresh rate.

How to fix it: Disable VSync, remove any FPS cap, and verify your monitor is running at its native refresh rate. If you want frame pacing without the input lag of VSync, use GSync or FreeSync instead.

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3. Your RAM Is the Hidden Bottleneck

When your RAM is too slow, running in single-channel mode, or you simply don't have enough of it, both the CPU and GPU end up waiting for data instead of processing frames. Neither can work at full capacity because neither is getting fed fast enough.

This shows up in our scans as high memory latency coupled with low CPU and GPU utilization. It's especially common on systems with:

• Single-channel RAM — one stick instead of two matched sticks. This halves your memory bandwidth and can reduce FPS by 10–25% in CPU-sensitive games.
• Slow RAM with XMP/EXPO not enabled — DDR5-6000 kit running at DDR5-4800 because the BIOS profile was never activated. Check our XMP/EXPO guide.
• Not enough RAM — if your system is using the pagefile (virtual memory on your SSD/HDD) because your 16 GB is full, performance craters. Task Manager → Performance → Memory will show if you're at capacity.

How to confirm: Run Task Manager and check Memory tab for speed, slots used, and total usage. If you see one stick in one slot, you're in single-channel. If the speed is lower than what your RAM is rated for, XMP/EXPO isn't enabled.

How to fix it: Enable XMP or EXPO in BIOS (usually one toggle in the main page), ensure you're running dual-channel (two sticks in the correct slots — check your motherboard manual), and consider upgrading to 32 GB if you're regularly maxing out 16 GB.

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4. The Game Is Poorly Optimized or Has a Known Engine Bottleneck

Some games simply don't use your hardware efficiently, and no amount of tweaking on your end will make them do so. This is increasingly common with Unreal Engine 5 titles, where the engine's rendering pipeline creates internal bottlenecks that prevent full hardware utilization.

Signs it's the game, not your PC:

• Other games run fine on the same hardware with high utilization.
• The game's subreddit or Steam forums are full of identical performance complaints.
• Performance is bad regardless of graphics settings — dropping from Ultra to Low barely changes FPS.
• The game just launched and hasn't received optimization patches yet.

What you can do:

• Switch graphics APIs if the game offers options. Try DirectX 12 vs. DirectX 11, or Vulkan vs. DX12. Different APIs have different overhead patterns, and one might distribute work across your CPU threads better. See our graphics API comparison.
• Enable shader pre-compilation if available. Some games compile shaders on-the-fly, causing stutters where both CPU and GPU drop utilization during compilation.
• Check PCGamingWiki for the specific game — community fixes often address performance issues before official patches.
• Wait for patches. It's not a satisfying answer, but it's honest. Unreal Engine 5 games in particular tend to improve significantly in the months after launch.

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5. Your Storage Is Creating a Pipeline Stall

When a game needs to stream assets — textures, models, audio — and your storage can't deliver them fast enough, the rendering pipeline stalls. The GPU waits for texture data, the CPU waits for asset decompression to finish, and both show low utilization even though neither is actually idle by choice.

This is most visible as:

• Stutters when entering new areas or turning the camera quickly.
• Low-resolution textures that slowly pop in to higher quality.
• Brief freezes followed by normal performance.

How to confirm: Open Task Manager → Performance → Disk. If your disk hits 100% active time during the stutters, storage is your chokepoint. Games installed on a traditional HDD are the most common case, but even a SATA SSD can struggle with modern open-world games that aggressively stream assets.

How to fix it:

• Move the game to an NVMe SSD. The read speed difference between a HDD (80–160 MB/s) and an NVMe drive (3,000–7,000 MB/s) is enormous. Even a budget NVMe SSD eliminates this bottleneck.
• Increase your RAM. More RAM means the game can cache more assets in memory instead of streaming from disk. Going from 16 GB to 32 GB reduces disk streaming pressure significantly in open-world titles.
• Disable on-demand texture streaming if the game offers it. Some games let you preload all textures at launch, trading longer load times for smoother gameplay.

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6. You Have a Power Delivery Problem

Your CPU and GPU won't boost to full speed if they aren't getting enough power, and they do this silently — no crash, no error message, just reduced clock speeds and reduced utilization.

Common power delivery issues:

• PSU wattage too low. A 500W PSU trying to feed an RTX 5070 and a Ryzen 7 9700X will force both components to throttle under load. Use a PSU wattage calculator to verify you have enough headroom — 20% above your system's peak draw is the minimum recommendation.
• Power plan set to Balanced or Power Saver. Windows' Balanced power plan dynamically scales CPU frequency, and the ramp-up delay can cause the CPU to run below maximum clock speed during mixed workloads. Set it to High Performance or use AMD's Ryzen High Performance / Ryzen Balanced plan.
• GPU power limit reduced. If you or a previous owner undervolted the GPU and also reduced the power limit, the GPU won't boost to full clocks. Check MSI Afterburner's power limit slider — it should be at 100% or higher for maximum performance.
• Laptop power mode. Gaming laptops on battery or set to "Better Battery Life" aggressively limit both CPU and GPU power. Plug in and switch to the performance power profile.

How to confirm: Use HWiNFO64 to monitor CPU and GPU clock speeds during gaming. If your CPU isn't hitting its rated boost clock, or your GPU clock is significantly below its boost specification, power delivery is the culprit.

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7. Background Software Is Interfering with GPU Scheduling

Windows' GPU scheduler distributes rendering work, and certain background processes can disrupt this scheduling in ways that reduce both CPU and GPU utilization without showing up as high-usage processes themselves.

The worst offenders:

• Hardware-accelerated browsers and apps. Chrome, Edge, Discord (with hardware acceleration), Spotify — each registers as a separate GPU context. The GPU scheduler time-slices between your game and these contexts, reducing peak utilization even if each background app uses minimal GPU time individually.
• Windows Desktop Window Manager (dwm.exe). This composites every window on your desktop and runs as a GPU process. With a multi-monitor setup, DWM's GPU overhead increases.
• Screen recording or streaming software that isn't using the dedicated hardware encoder properly. OBS using x264 (CPU encoding) instead of NVENC/AMF can steal both CPU and GPU resources in unexpected patterns.
• Overlay software stacking. Running Steam overlay + Discord overlay + GeForce Experience overlay + MSI Afterburner overlay simultaneously adds multiple GPU contexts and draw calls per frame.

How to fix it:

• Close unnecessary hardware-accelerated apps before gaming.
• Use only one overlay at a time. We recommend MSI Afterburner alone for monitoring.
• If you stream, verify OBS is using NVENC (NVIDIA) or AMF (AMD) hardware encoding, not x264.
• If you game on a single monitor, consider disconnecting or disabling extra monitors while playing — it reduces DWM overhead.

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How to Diagnose Your Specific Case

If you've read through all seven causes and aren't sure which applies to you, here's a quick diagnostic path:

1. Check per-core CPU usage (not overall). If one core is at 100%, it's cause #1.
2. Disable all frame rate caps and VSync. If performance jumps, it was cause #2.
3. Check RAM configuration — dual-channel? XMP enabled? Enough capacity? If any fail, it's cause #3.
4. Test another game. If only one game has the issue, it's cause #4.
5. Monitor disk usage during stutters. If the disk spikes, it's cause #5.
6. Watch clock speeds with HWiNFO64. If CPU or GPU isn't hitting rated boost, it's cause #6.
7. Close everything except the game. If performance improves significantly, it's cause #7.

Or save yourself 30 minutes: run your system through our free PC bottleneck analyzer and it will identify which component is holding you back — even when the answer isn't obvious from raw utilization numbers.

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The Bottom Line

Low CPU and GPU usage with poor performance almost always means there's a bottleneck somewhere else in the pipeline — a single thread, your memory, your storage, your power delivery, or the game itself. The fix depends entirely on identifying which pipeline stage is stalling, and overall utilization percentages won't tell you that on their own.

The good news: most of these fixes are free. Enabling XMP, removing a frame cap, closing background apps, and switching to per-core monitoring costs nothing and solves the problem for the majority of people we see with this issue.

Analyze your PC for free — it takes about 30 seconds and catches bottlenecks that Task Manager misses.