TRADE CHAT The problem with the PC is power…
AS THE FANS INSIDE my Intel eight-core laptop spooled up to their customary mini-hurricane mode, it reminded me that the PC has a major problem with power efficiency. I had a couple of Chrome windows open running 10 tabs each. That’s pretty much all it takes for my laptop to freak out now.
Admittedly, this laptop is powered by Intel’s 11th gen rather than 12th gen CPU architecture. But 11th gen chips are still built on Intel’s latest 10nm production process. And if there’s one thing that 12th gen Alder Lake sucks at, it’s power efficiency. Give the 12900K desktop model a hammering and it guzzles as much as 300W while hitting 100°C.
Not that Intel is alone in producing silicon power hogs. Nvidia’s Geforce RTX 3090 can breach 350W, while the new 3090 Ti can hit over 500W. AMD’s current graphics boards are little better. The Radeon 6900 XT will happily suck down 325W or so.
Next-gen GPUs due later this year are expected to be even worse. The Nvidia GeForce RTX 4090 is rumored to be a 600W board. A mooted 4090 Ti variant could possibly come in above 800W. Now imagine a scenario with a maxed out 3090 Ti running in the same rig as an Intel 12900K CPU also under full load. The total system power consumption would be getting close to the recommended 1,440W limit for continuous power from a standard US wall socket.
It’s the sort of power consumption that gets you thinking about environmental issues, not to mention cost issues. I mean, have you seen oil and gas prices lately? It’s a parlous state of affairs given chip manufacturing processes continue to advance. That next-gen Nvidia 40 series GPU is expected to be produced on TSMC’s latest 4nm node, for instance. It’s hard to understand how things have gotten so bad.
It doesn’t have to be this way— and, yes, I’m going to mention Apple silicon. The latest MacBook M1 Air makes every x86-powered PC laptop look ridiculous. Its single-core performance is as good as anything this side of Intel Alder Lake. With four performance cores and four efficiency cores, the multi-threaded performance isn’t bad either. It does this in a slim chassis with no active cooling that barely gets warm or throttles.
It uses about 30W totally strung out, but that’s the whole laptop, not just the M1 chip. As for the higherperforming M1 chips, they are just as impressive. The M1 Max fitted to a 16-inch MacBook Pro hasn’t quite got the multi-threaded grunt of, say, an Intel Core i9-12900HK mobile CPU. But it’s competitive in most benchmarks. And if there’s a 12900K-powered laptop that has even half the battery life of the
MacBook, I haven’t seen it. Most have a third or a quarter of the battery life, or even worse.
At the core of the problem on the CPU side of the equation is the x86 ISA. There’s no avoiding the fact it’s both ancient and wasn’t originally conceived with power efficiency in mind, unlike the ARM instruction set used by Apple silicon that was all about efficiency. Of course, until recently, that focus on efficiency has seemingly prevented an ARM chip from competing on pure performance. Clock-for-clock, in the single-threaded workloads the cores in M1 are more powerful even than Alder Lake. If Apple starts cranking up the clocks and chucking a load of cores in a future Mac Pro, it should be interesting.
Anyway, that’s not to say Apple is going to take over the world and replace our beloved PCs with Macs. But the PC does have a power problem that desperately needs solving. The ever-increasing power consumption of the latest CPUs and GPUs cannot continue. If x86 can’t up its game, maybe it’s finally time that long-mooted transition from x86 to ARM for the PC actually happens.
Six raw 4K panels for breakfast, laced with extract of x86... Jeremy Laird eats and breathes PC technology.
The ever-increasing power consumption of the latest CPUs and GPUs cannot continue.