Laptop gpu VS desktop power usage ?

[The321]

Alot of laptop gpus are almost as good as their desktop counterpart but only use a fraction of the power how is this possible ?

[PineyCreek]

Examples of what you mean?  Most GPUs in laptops are a specific mobile variant of the GPU line.

[crosstiger]

They are still quite far away from desktop great performance. For example a notebook 1060 is nowhere near as good as a desktop 1060. Sometimes the gap is as big as 20-30%.

 

Notebook gpus run mostly at lower clock speeds at lower voltage. A mobile 1060 clocks at around 1400 - 1700 MHz while desktop cards can runs at 1800 - 1900 MHz. This is mainly because they are limited in power. A notebook power brick might deliver ~150 - 200W where the gpu gets around 100W. Of course this depends on the manufacturer. If you take a super thin ultrabook it might be limited to far less that 100W of power. A desktop gpu can use more than 200W of power if required.

 

Also cooling is a big factor. Notebook chips can run at nearly 80 – 100C. With gpu boost 3, the card will lower its clock speed much earlier than on a desktop part leading to reduced performance over time.