[BUG] Windows: Active Claude Code agent pegs iGPU depending on visible Claude Desktop window size

Preflight Checklist

• [x] I have searched existing issues and this hasn't been reported yet
• [x] This is a single bug report (please file separate reports for different bugs)
• [x] I am using the latest version of Claude Code

What's Wrong?

What's Wrong?

This may be related to #67670, #26302, #58817, #66495, #56805 and #51955, but I am filing a separate Windows-specific issue because the trigger is different and reproducible.

Claude Desktop on Windows causes high sustained Intel iGPU usage only while a Claude Code agent is actively running and the Claude Desktop window is visible.

This does not appear to be caused by the project workload itself, local AI computation, mouse control, or visible GUI test automation. The GPU load is tied to the visible Claude Desktop window area during an active Claude Code agent run.

Observed behavior:

• Windows laptop with Intel integrated GPU + NVIDIA dedicated GPU.
• Claude Desktop version: 1.12603.1 (3df4fd).
• Claude Code agent active + Claude Desktop window fully visible: Intel iGPU / GPU 0 / 3D rises to very high sustained usage, around 90–95%.
• Claude Code agent active + Claude Desktop window reduced to about 20% of visible screen area: GPU usage drops significantly, around 50%.
• Claude Code agent finished: GPU usage drops back down.
• The GPU-consuming process is Claude.exe.
• This also happens with small prompts.
• It happens without explicitly asking for mouse control, screen automation, visible GUI tests, or any local GPU-heavy workload.
• If the Claude Desktop window is hidden, minimized, or mostly covered, GPU usage drops substantially.

This suggests that the active Claude Code agent UI triggers a continuous renderer/compositing/repaint loop, and the cost scales with the visible Claude Desktop window area.

Expected Behavior

Claude Desktop should not peg the integrated GPU merely because a Claude Code agent is active and the Desktop window is visible.

The UI should render efficiently during active agent runs, or provide a user-facing setting to disable hardware acceleration / GPU compositing.

Actual Behavior

During active Claude Code agent runs, Claude Desktop appears to continuously repaint/re-render the visible window.

The larger the visible Claude Desktop window area, the higher the Intel iGPU usage. When the agent finishes, the GPU usage drops back down.

Steps to Reproduce

1. Use Windows 11 on a laptop with Intel iGPU and NVIDIA dGPU.
2. Start Claude Desktop.
3. Start a Claude Code agent task.
4. Open Windows Task Manager and enable the columns "GPU" and "GPU engine".
5. Keep the Claude Desktop window fully visible.
6. Observe Claude.exe using GPU 0 - 3D at very high sustained usage.
7. Resize or cover the Claude window so only about 20% remains visible.
8. Observe GPU usage dropping significantly.
9. Let the Claude Code agent finish.
10. Observe GPU usage dropping back down.

Environment

• OS: Windows 11
• GPU 0: Intel integrated GPU
• GPU 1: NVIDIA dedicated GPU
• Claude Desktop version: 1.12603.1 (3df4fd)
• Claude Code version: [insert if shown separately]
• Installation type: [Microsoft Store/MSIX or claude.com download]
• Laptop model: [insert laptop model]
• Power state during observation: [charger plugged in / unplugged]
• Note: When unplugged, the NVIDIA dGPU may be disabled by the laptop power profile, so Claude Desktop falls back to the Intel iGPU. However, the core issue is that the GPU load appears to be driven by the visible Claude Desktop window during an active agent run.

Related Issues

Possibly related, but not the same trigger:

• #67670: Windows/MSIX multi-GPU cursor stutter/lag over Claude Desktop window
• #26302: Windows foreground UI lag / mouse stutter
• #58817: Large desktop app window size pegs iGPU, but reported on Linux
• #66495: Windows / NVIDIA renderer degradation
• #56805: Windows / Electron GPU compositing / DWM behavior
• #51955: Windows dual-GPU laptop using integrated GPU instead of NVIDIA

The difference in this report is the specific reproducible trigger:

active Claude Code agent + visible Claude Desktop window area = sustained Intel iGPU load

Workaround

Minimizing, hiding, or mostly covering the Claude Desktop window during active agent work reduces GPU usage substantially.

A user-facing "Disable Hardware Acceleration" or "Disable GPU Compositing" setting would likely help.

What Should Happen?

Claude Desktop should reduce GPU usage and power consumption during active Claude Code agent runs.

When a Claude Code agent is active and the Claude Desktop window is visible, Claude.exe should not cause sustained high Intel iGPU usage or "Very high" power usage in Windows Task Manager.

Expected behavior:

• GPU usage should stay at a reasonable level during normal active agent work.
• Power usage should stay at a reasonable level during normal active agent work.
• The visible size of the Claude Desktop window should not cause GPU usage and power usage to rise dramatically.
• Reducing, covering, or minimizing the Claude Desktop window should not be necessary to avoid high GPU and power usage.

Error Messages/Logs

Steps to Reproduce

1. Use a Windows 11 laptop with an integrated Intel GPU and a dedicated NVIDIA GPU.

1. Start Claude Desktop.

• Claude Desktop version used here: 1.12603.1 (3df4fd)

1. Open Windows Task Manager.

1. In Task Manager, enable these columns:

• GPU
• GPU engine
• Power usage
• Power usage trend

1. Open the Claude Desktop Code tab / Claude Code agent view.

1. Start a minimal Claude Code agent task in any local folder. No special project, GUI test, browser automation, image processing, or local GPU-heavy workload is required.

Example prompt:

```text
Create a file named gpu-repro.txt containing the text "gpu repro test". Then read it back, inspect the current folder, and report what you did. Do not use browser automation, mouse control, screen automation, GUI tests, image processing, or any visible UI testing.
While the Claude Code agent is actively running, keep the Claude Desktop window fully visible on screen.
Observe in Task Manager:
The GPU-consuming process is Claude.exe.
GPU engine shows GPU 0 - 3D.
Intel iGPU usage rises to very high sustained usage, around 90–95%.
Power usage for Claude.exe is shown as "Very high".
Without stopping the agent, reduce or cover the Claude Desktop window so that only about 20% of the window area remains visible.
Observe that GPU usage drops significantly, but still remains around 50%, which is still high for a mostly text-based UI.
Observe that power usage also remains high/very high while the agent is active and the Claude Desktop window is still partly visible.
Minimize or hide the Claude Desktop window while the agent is still active.
Observe that GPU usage drops substantially.
Let the Claude Code agent finish.
Observe that GPU usage and power usage drop back down after the agent is no longer active.
Repeat with another small prompt that does not involve GUI work, screen automation, browser automation, image processing, or local GPU-heavy work. The same behavior occurs: the GPU and power usage are tied to active agent work plus visible Claude Desktop window area, not to the project workload itself.

Claude Model

Not sure / Multiple models

Is this a regression?

I don't know

Last Working Version

Version 1.12603.1 (3df4fd)

Claude Code Version

Version 1.12603.1 (3df4fd)

Platform

Other

Operating System

Windows

Terminal/Shell

PowerShell

Additional Information

_No response_