News for hackers. Stuff that matters.

A comment on Intel 3rd gen Xeon Scalable (Ice Lake): generationally big, competitively small. Parent comment

Re:Intel 3rd gen Xeon Scalable (Ice Lake): generationally bi... by neogodless on Tuesday April 06, 2021 @02:41PM (#26715646)
A bit off topic from the server CPU discussion, but I was curious how well AMD is advancing idle power consumption.

For example, the Ryzen 3000 desktop chips seemed to have the issue[0], but the same Zen 2 cores seem to have found some improvements in the Ryzen 4000 mobile chips[1].

I didn't want to just rely on Reddit forum comments, so I found this measure of the Ryzen 3600[2].

> When one thread is active, it sits at 12.8 W, but as we ramp up the cores, we get to 11.2 W per core. The non-core part of the processor, such as the IO chip, the DRAM channels and the PCIe lanes, even at idle still consume around 12-18 W in the system.

My interpretation was expect ~12 W or more idle consumption (just from the CPU package), but I'm not sure I understand it correctly.

I couldn't find the same information for Ryzen 4000 laptops, but the same APU is tested in a NUC, where the total system draw (at the wall) at idle was about 10-11 W, still nearly double that of a Core i7 U-series NUC[3], but certainly lower than that of just the CPU package in the Ryzen 3600.

Anecdotally, my 45W Ryzen 7 4800H laptop with 15.6" 1080p screen lasts about 4 hours on 80% of the 60Wh battery with 95% brightness, doing various non-intensive tasks. Though I don't know how well the battery holds up on complete non-use standby.

[0] https://old.reddit.com/r/AMDHelp/comments/cfm1xa/why_is_ryze...

[1] https://old.reddit.com/r/Amd/comments/haq4fg/the_idle_power_...

[2] https://www.anandtech.com/show/15787/amd-ryzen-5-3600-review...

[3] https://www.anandtech.com/show/16236/asrock-4x4-box4800u-ren...

[ Parent | on HN ]
Re:Intel 3rd gen Xeon Scalable (Ice Lake): generationally bi... by wtallis on Tuesday April 06, 2021 @02:52PM (#26715813)
Ryzen 3000 desktop processors use a chiplet design, with the IO die built on an older process than the processor dies. Ryzen 4000 mobile processors are monolithic dies, so they don't have the extra power of the inter-chiplet connections and they're entirely 7nm parts instead of a mix of 7nm and 14nm.
[ Parent | on HN ]
Re:Intel 3rd gen Xeon Scalable (Ice Lake): generationally bi... by bkor on Tuesday April 06, 2021 @02:52PM (#26715808)
> I couldn't find the same information for Ryzen 4000 laptops

I measured an Asus Mini PC PN50 with a Ryzen 4500U. The idle power usage was 8.5 Watt for the system. This with 32GB of memory and a SATA SSD installed. It would be nice if it was lower than this, but it isn't too bad. Interestingly the machine used 1.2 Watt while off after it wasn't on power, 0.5 Watt after starting up and shutting it down.

Recently noticed some people focussing on low power but powerful 24/7 home "servers". Systems that are on 24/7, but often idle. One system used around 4.5 Watt in idle. The "brick" / power adapter often uses too much power, even when everything is off.

[ Parent | on HN ]
Re:Intel 3rd gen Xeon Scalable (Ice Lake): generationally bi... by ajross on Tuesday April 06, 2021 @07:21PM (#26718579)
It's worth noting the difference in tone from the bulk of the discussion in this thread.

Objectively, Ice Lake "isn't too bad" in comparison with Zen 3 either. "It would be nice if it" drew a 20% less power at load, but in practice you could use either product without trouble.

[ Parent | on HN ]
Re:Intel 3rd gen Xeon Scalable (Ice Lake): generationally bi... by bcrl on Tuesday April 06, 2021 @08:34PM (#26719125)
In order to satisfy their wafer supply agreement with Global Foundries, AMD ships a GF fabbed I/O die in all their volume processors. I'm pretty sure that once they have met the terms required to exit that wafer supply agreement, we will see AMD shift that I/O die to a newer process with lower power draw.
[ Parent | on HN ]