Really this can apply to any CPU. Why can’t we just put one of those in a mobile device? It’s small enough. Is it heat and cooling issues? Or something else entirely? If we can put one of those in a mobile device it would be an absolute game changer
In: Technology
The two biggest limiting factors are power consumption and cooling. Smartphones are battery powered and passively cooled (they have no fans). So they favour efficiency over raw power.
Heat is essentially wasted electricity, so power consumption and temperature regulation go hand in hand. This means basically that different architecture CPUs are better in different use cases. In PCs we have a more powerful energy source and we use that for active cooling with fans or water and so we focus on raw speed at the expense of heat generation. In mobile phones we mostly want long battery life so we have to settle for less CPU speed.
Size is definitely an issue. Phones are packed to the brim with electronics, there’s not really space for a big cpu. Cooling and power are both issues, phone cpus are fairly power/heat efficient for their size. You can’t really slap a heatsink onto a phone like you can a computer. Plus, even if you could dissipate enough heat, the surface of the phone is the heatsink, and it would become uncomfortably or dangerously hot to hold.
Cell phones need low power chips. That’s one of the biggest design requirements, in fact almost everything revolves around that.
Low power CPUs make your battery life last longer and require less heat dissipation. Intel amd64 CPUs running at 3GHz have nowhere near the low power requirements.
You could put any CPU you wish into a mobile device. But, as you guessed, power is a major issue for mobility.
Firstly desktop CPUs chew up a lot of power. And that power is turned into heat – which is why most modern desktop CPUs have large fans attached – to dissipate the energy into the air.
Even if you put a big fan on the back of a CPU in a mobile device you really don’t want a lot of heat in your pocket. So that puts quite a limit on the power that a phone can dissipate safely.
And we haven’t even talked about the size of a battery required to power a desktop CPU – which would be considerable.
You’re not wrong that desktop CPUs are small. It’s true. But it’s really all down to power supply and heat dissipation.
And cost/price.
The battery can run it for 5 minutes. By then, you have to put it down because it’s so hot, so you might as well shut it down and recharge it. Who wouldn’t want that.
As an addendum to this question, with people talking about efficiency, all else being equal, is a multicore processor more power efficient than a single core? I.e does it use less power to gain processing power through parallelism rather than raw clock cycles?
Main issues are power and cooling.
A mobile device is super compact, so there’s no internal airflow or ability to add fans.
Even if you could somehow dissipate the heat, people expect their phone’s power consumption to allow going a certain amount of time without a charge. With a high-speed power-hungry CPU, you’d need a big battery, which wouldn’t fit.
Latest Answers