NL-2610.004Result[nl.MM]
An "8 GB" graphics card reports 7.99 GiB, and the desktop may be using half of it
The Nook team
Submitted 5 October 2026 · 2 min read
When we added more video models to Nook, each listed with the video memory (VRAM) it needs, none of the 8 GB models was marked as fitting our 8 GB card. The RTX 4060 reports 8188 MiB, which is 7.99 GiB, so a strict comparison failed by a few megabytes. Nook now allows half a gigabyte of slack when it compares a model's needs with the card. While testing, we also found about 4.7 GB of the card already in use by desktop apps before any model loaded. The number on the box says little about what a model will actually find free.
- Comments
- RTX 4060 8 GB, Windows 11. Two readings from one machine, not a survey.
- Subjects
- Memory (nl.MM); Images and video (nl.VI)
- Cite as
NL-2610.004· usenook.ai/labs/what-8-gb-means.html
Full text
An “8 GB” card reports slightly less than 8 GiB, so checks need some slack; Nook allows half a gigabyte. What matters more is what is free: on our card, desktop apps were once holding 4.7 GB of the 8.
What we found
Nook's Video page lists each model with the memory it needs and marks it “Fits your GPU” or “Needs a 16 GB GPU”. After we added Wan 2.2 TI2V 5B, listed as needing 8 GB, it showed as not fitting our 8 GB RTX 4060. The card was not too small; the check was too strict.
| Reading | Value |
|---|---|
| On the box | 8 GB |
| Reported by the driver | 8188 MiB = 7.99 GiB |
| 8 GiB exactly | 8192 MiB |
| In use by desktop apps, one afternoon | about 4.7 GB |
| Left for a model then | about 3.3 GB |
The card reports 4 MiB less than 8 GiB, so “needs 8” compared with “has 7.99” said no. Model makers round in their own ways too: a model listed for 8 GB is meant for 8 GB cards.
What we changed
Nook now counts a model as fitting when the memory it needs is no more than the card's memory plus half a gigabyte. The same rule is used in the app's engine and in its interface, so the mark and the setup agree.
What it means on your machine
- Look at what is free, not at the label. Task Manager's Performance tab shows it under GPU, or ask the driver:
nvidia-smi --query-gpu=memory.total,memory.used,memory.free --format=csv- Close what holds video memory before a big job: browsers with hardware acceleration, games, video calls, screen recorders.
- If what is left is less than the model needs, on Windows the job will most likely crawl rather than fail. NL-2610.002 explains why, and how to tell.