GPU memory (VRAM)

This chapter describes a real operational issue, not a rare edge case. If you run four tiles of high-resolution video on a busy machine, read it — the symptom looks exactly like an app fault but isn’t, and knowing what it is saves a lot of confusion.

Why it matters

Decoding video is done on the graphics card, and every open tile needs its own working space in the card’s dedicated memory (VRAM). Four tiles of 1080p60 decoding at once is a genuinely heavy load. If the card runs short of VRAM — because other programs (browsers especially) are using it too — Windows starts shuffling video memory in and out to cope, and frame delivery collapses.

The tell-tale symptom is distinctive: the pictures freeze or stutter and the tiles drift apart, while the audio keeps playing perfectly normally. Sound comes from ordinary system memory, so it sails on; only the video, starved of VRAM, falls behind. It looks like the app has locked up or lost sync, but nothing is wrong with the app — the graphics card has simply run out of room. As soon as VRAM is freed, playback returns to normal on its own.

The VRAM indicator

To make the pressure visible before it bites, the top-right tool cluster shows a small VRAM readout: how much of the card’s memory is in use out of its total, the percentage, and the app’s own share. It updates every few seconds and is colour-coded:

Clicking the readout lists the processes using the most GPU memory right now, so you can see what’s eating it. (One entry, the Windows desktop compositor dwm, often shows a very large figure — this counts memory associated with other applications’ windows too, so don’t read it as a single runaway program.)

When you load a video or switch mode and free memory is below what’s needed, the app also raises a brief “GPU memory low” warning over the video area, so a starved session is flagged up front rather than discovered mid-review.

The VRAM readout in the toolbar (green here, meaning comfortable headroom), and the list of top GPU-memory consumers shown when you click it.
The VRAM readout in the toolbar (green here, meaning comfortable headroom), and the list of top GPU-memory consumers shown when you click it.

On integrated graphics (many laptops)

Not every machine has a dedicated graphics card. Many laptops use integrated graphics, where the GPU is built into the processor and has little or no memory of its own — instead it borrows a large slice of the computer’s system memory (RAM) as needed. This is normal and works fine.

On such a machine the indicator measures that shared memory rather than a near-zero dedicated figure, and labels itself “GPU mem (shared)” so you can tell the two apart. The numbers then show how much of the shared budget is in use — usually a comfortable fraction, because that budget is typically many gigabytes.

Everything above still applies, with one change of emphasis: because the GPU is sharing system memory, “close other programs” here means freeing system RAM, not a separate video card. If shared memory ever runs low it’s the same situation as the machine running low on memory generally — close memory-heavy applications. In practice integrated machines rarely hit this, and the indicator usually just confirms there’s plenty of headroom.

(If the app can’t tell for certain what kind of graphics it is running on, it shows the reading without a warning rather than risk a false alarm.)

What to do about it

First, close GPU-heavy applications. Web browsers are usually the worst offenders — a browser with many tabs, or one playing video, can hold gigabytes of VRAM. Close them (not just minimise) and watch the indicator; if it drops back to green and playback recovers, you’re done.

If closing programs doesn’t recover it, log out and back in, or restart Windows. This is the part that surprises people: some VRAM allocations are not released just by closing the applications that caused them. Certain drivers and background components — virtual-display and remote-desktop software are common culprits — leave memory committed that only a fresh Windows session reclaims. If the indicator stays high with everything closed, a sign-out/sign-in or a reboot resets the allocations and gives you the whole card back. It’s the reliable cure when closing apps isn’t enough.

In short:

  1. Watch the indicator; treat red as a warning to act.
  2. Close browsers and other GPU-heavy apps.
  3. If it’s still high, sign out and back in, or restart Windows.

None of this is the app misbehaving — it’s the graphics card being shared with everything else on the machine. The indicator just makes that sharing visible.