Local AI image generator on your PC: how long one picture takes
Short answer: on a gaming PC with a decent graphics card, about half a minute. On a normal 16 GB laptop, 2 to 3 minutes. On an 8 GB laptop, it won't work.
The test
Same picture AI on every PC (Z-Image Turbo, run inside GreenCube), a 512 by 512 picture, 8 steps. We timed from pressing the button to the finished picture, in September and October 2026.
| PC | What did the work | Time per picture |
|---|---|---|
| Desktop, 12 GB card, 32 GB RAM | Graphics card | 28 s |
| Laptop, Core Ultra 5, 16 GB | Built-in Intel graphics | 2 min 22 s – 2 min 38 s |
| Same laptop | Processor only | 11 min 27 s |
| Laptop, 8 GB | — | Can't |
The bars show speed, so longer is faster.
What we learned
1. Any graphics helps a lot
Even the small graphics chip built into the laptop made pictures about 4 times faster than the processor alone. A real graphics card is another 5 times faster on top of that.
2. It needs about 7 GB of room
The picture AI asks Windows for about 7 GB while it works. That's why an 8 GB laptop can't do it, and why GreenCube checks there's room before it starts instead of crashing halfway.
3. Your other apps don't matter much
On the 16 GB laptop we made the same picture with a code editor and a browser open, and even with 4 GB taken up on purpose. It still took about 2 minutes every time. Windows moves idle stuff aside.
What your PC will feel like
Graphics card
Under a minute per picture. Make lots and pick the best one.
16 GB laptop, no card
2 to 3 minutes. Fine for a few pictures; start one and keep studying.
8 GB laptop
No pictures. Chat and study still work.
No limit either way
Nothing counts your pictures. The only limit is how long you want to wait.
Questions
How long does it take to make an AI picture on my PC?
In our tests, a 512 by 512 picture took 28 seconds on a desktop with a 12 GB graphics card, about 2 and a half minutes on a 16 GB laptop using its Intel graphics, and about 11 and a half minutes on the same laptop's processor alone.
Can I make AI pictures on a laptop without a graphics card?
Yes, if it has 16 GB of RAM. Built-in Intel graphics made it about 4 times faster than the processor alone. With 8 GB of RAM it won't work: the picture AI needs about 7 GB by itself.
Do I need to close other apps to make AI pictures?
Not on a 16 GB laptop. With a code editor and a browser open, the picture took the same time. What matters is that Windows can set aside about 7 GB for it.
Your own AI, on your own PC
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