Owners of laptops fitted with Intel's Core i9 high-performance processor, including computers made by Apple and Dell, are finding that the machines slow down compared to the pace of older models.
Chipzilla describes the six-core Core i9 as a "no compromises" chip aimed at gaming, VR and "next-level content creation". Intel has introduced a new feature intended for burst workloads – Thermal Velocity Boost (TVB) – that adds 200MHz in clock cycles to the standard 4.6GHz of TurboBoost. Intel has said in briefings that TVB will run only if the processor temperature allows it to – that is, it's below 50°C (122°F) – and that the processor speed may then drop in response to a temperature spike.
In other words, if the chip is cool enough, and a burst of work has to be done, the CPU cores can speed up, but then may need to slow right down to cool off.
TVB, according to Intel (PDF), "opportunistically and automatically increases clock frequency by up to 200MHz if the processor is at a temperature of 50°C or lower and turbo power budget is available. The frequency gain and duration is dependent on the workload (best for bursty workloads), capabilities of the individual processor, and the processor cooling solution. Frequencies may reduce over time and longer workloads may start at the max frequency but drop as processor temperature increases."
Dell sells the Core i9 in its XPS 15 models, starting at £2,398.99, and Apple in its newest MacBook Pro models, where it's a £360 build-to-order option on the 15-inch models.
But owners of high-cost machines are finding issues.
A thread on Reddit suggests that Dell machines are experiencing a drop in clock frequency when taxed.
"The cooling solution for the form factor of the XPS 15 is insufficient for the amount of heat that the laptop creates when gaming. You will experience some sort of throttling," one Dell owner claimed on the XPS subreddit.
YouTuber Dave Lee illustrates how the throttling – which isn't new – takes the performance of the new MacBook Pro models equipped with the premium chip to below that of last year's i7:
"This i9 in the MacBook can't even maintain the base clock speed. Forget about Turbo Boost, it can't even maintain the 2.9GHz base clock speed, which is absurd. This CPU is an unlocked, overclock-able chip, but all of that CPU potential is wasted inside this chassis," Lee said.
"Apple shouldn't have caved to pressure and shouldn't have touched Coffee Lake with a ten foot pole," another Mac user mourned, referring to the eighth-gen Intel lineup.
We requested comment from Intel, Apple and Dell on what advice owners of the expensive machines should expect.
"Customer feedback is very important to us and we are working closely with our OEM partners to investigate. We will share more information when it is available," Intel told us. Dell and Apple had yet to respond at press time. ®