Alder Lake Allegedly Commands 28% Higher Peak Current Than Rocket Lake

Image of the rear of a power supply.
(Image credit: Shutterstock)

FCPOWERUP, a Chinese media outlet that specializes in power supply reviews, has reportedly shared the power level requirements for Intel's 12th Generation Alder Lake chips. The publication has a pretty solid record in terms of leaks as it was the first to publish the schematics and photograph of Nvidia's then-unreleased 12-pin PCIe power connector.

The tables appear to have originated from one of Intel's confidential documents that's probably directed towards power supply vendors. The information allegedly specifies the power recommendations for the 12V2 power rail, which feeds the processor. Funnily enough, the table lists the specifications for 165W, 125W, 65W and 35W processors. Intel didn't port either Comet Lake or Rocket Lake to the HEDT space, so we can ignore the 165W recommendations. Furthermore, it's very unlikely that the chipmaker will launch Alder Lake in the HEDT format. At any event, take the information with a bit of salt.

The continuous current ratings for the Alder Lake 125W, 65W and 35W SKUs are identical to those of Comet Lake and Rocket Lake. The peak current ratings, however, show increases up to 28% (approximately between 50W to 100W). Peak current refers to the maximum amount of current that can be sourced during brief periods of time , while continuous current represents the amount of current that's continuously supplied.

Intel Alder Lake Power Requirements (Image credit: FCPOWERUP/Weibo)

The peak output for the 125W SKU increased from 34A (408W) to 39A (468W), while the 65W SKU went from 30A (360W) to 38.5A (462W). Even the energy-efficient 35W SKU jumped from 16.5A (198W) up to 20.5A (246W).

The transition from Rocket Lake to Alder Lake reveals a 15% higher recommended peak current capacity at the 125W tier, 28% at the 65W tier and 24% at the 35W tier. The duration depends on the PL4 of the processor. Intel specifies that the 12V2 should be able to supply peak output for 10 milliseconds. Again, it's important to emphasize that only the peak current values went up as the continuous current values remained untouched. This information is important for power supply manufacturers to ensure that their products comply with the power specifications for the upcoming Alder Lake chips.

Power supplies with a single-rail design delivers everything through a single 12V rail. The problem lies with older multi-rail power supplies where their 12V rails still adhere to the 20A (240VA) output limit. By default, the over current protection (OCP) is set to 30A and will activate for loads over 30A.

So, what does this really mean for Alder Lake adopters? FCPOWERUP noted that consumers may have to add between 50W to 100W to their power budget, depending on the exact model of the Alder Lake processor. If possible, you should opt for a power supply single-rail design as it's less likely to have that problem with the 20A limit on the 12V rails.

As we near the end of the year, more and more Alder Lake benchmarks and leaked Intel 600-series motherboards have started to pop up in the wild. Alder Lake qualification samples are secretly being sold in the Chinese black market. All these recent occurrences imply that we may see Intel's hybrid desktop chips by the end of the year, and if not then early next year.

Zhiye Liu
News Editor and Memory Reviewer

Zhiye Liu is a news editor and memory reviewer at Tom’s Hardware. Although he loves everything that’s hardware, he has a soft spot for CPUs, GPUs, and RAM.