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Comment by coder543 | Hacker News Reader

Single threaded tasks should never run at the base clock. The base clock can pretty much be thought of as the minimum clock speed you should see when all cores are maxed out and the thermal solution is only just meeting the spec.

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I still want my computer to remain responsive even when I'm rendering in the background.

I doubt 2.5ghz vs 4.2ghz is going to make any real difference to "responsiveness". The more pressing concern would be making sure the kernel actually schedules foreground workloads promptly.

Maybe i'm missing why it doesn't matter. Ryzen runs at 4.5 base clock, TR Pro runs at 2.5 base clock, upon booting up nothing is happening so each cpu runs at their base clock. I open something like visual studio that isn't too intensive so each cpu doesn't realize it needs to boost. Won't the ryzen with 4.5 base clock feel snappier than the 2.5 one when vs loads?

When a pretty big task (compiling, rendering) activates the scheduler and causes the cpu to boost to their respective 5 ghz or w/e, then yeah the numbers would be the same, but they don't be at the beginning when i'm dragging windows around and right clicking on stuff in visual studio. I don't believe this feeling is reflected in the scores.

No. None of what you're writing is accurate. No processor made in the last decade will ever idle at the base clock. Any modern processor idles far, far lower than that, approximately 1Ghz, maybe even lower. Idling at multiple gigahertz would be a huge waste of energy. The minimum clock speed is not correlated to the "base clock" at all.

It takes tens of milliseconds to reach the boost clock: https://stackoverflow.com/a/64254459

The base clock is entirely irrelevant to everything you are talking about. Please reference my earlier comment for the meaning of "base clock": https://news.ycombinator.com/item?id=37980293

While technically correct for longer time frames, setting a performance governor on both windows and linux basically means that it comes out of idle at the max allowable frequency. In order to achieve this it basically means that idle isn't adjusting the clock rates (to avoid the transition latencies) for idle times less than 2x those latencies. Depending on the core/firmware/etc it may be gating the clock, or clock skipping, which can save some power

And yes it can waste energy you can measure with the your battery monitor (or UPS/PDU) but its also possible to measure the interrupt handling latency/etc, and for some cores it can make a very noticeable difference to desktop latency if you happen to be sensitive to such things.

While I've posted elsewhere about clamping the clock rate to save power, I also do the converse when plugged in by cutting off the bottom 2/3rds of the frequency range. This results in a far more responsive desktop in linux and even windows to a lesser extent.

Interesting, i'l l have to do more research here since the reason i went with my current setup is based on this thinking.

Typical desktop OS's don't have proper prioritization and terrible schedulers. It's definitely not the hardware.

>> and the thermal solution is only just meeting the spec.

Ok, so, as I alluded to earlier... make sure to have better-than-minimum-spec cooling to let the processor indefinitely run all cores at the boost clock (or very close to it).

It's been a long time since I've seen a desktop/workstation processor limit itself to the base clock for any reason.

Also, I agree with dralley. Clock speeds are unlikely to be the issue there anyways.

+1. it's great that it compiles code faster, but i would also like when i'm writing code and hit enter, a newline is added and all lines under it goes down by 1 without any "lag".

That's why i decided to go with a 5950x + 3090 rtx + gamer ram for my current "workstation" instead of a 5995wx + rtx 6000 + ecc ram for my current machine. even tho its not workstation rated, it seemed like the better way to go for quality of life feel.

When the next generation of cpu/gpu/ram drops in the next couple eyars, i can re-evaluate the gamer vs professional offering to see if it matters.

Having run a 3945WX machine side by side with same era intel and AMD desktops the Threadripper Pro was the more “responsive” machine, but it was minor enough you would have had to have them side by side to really notice.

Once there were a lot of programs in flight it started making a larger and larger difference. Now half my family and friends have TR Pro systems bought refurbished (they watched eBay) because they loved mine so much.

The TR Pro cpus with the same cores as ryzen equilivalent should have similar performance as they have similar specs.

https://www.amd.com/en/products/cpu/amd-ryzen-threadripper-p... vs https://www.amd.com/en/products/cpu/amd-ryzen-9-7900x

Its usually the ones with more cores than the max ryzen cpus that have to make tradeoffs and seeing how it affects day to day use. (the 32, 64, and in this case the 96 core ones).

That's more of a software thing than hardware. You could do that in the 80's with the right software, but most modern operating systems suck at realtime stuff (and ui is realtime).

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