Ryzen 3000 Boosting behaviour in Ryzen Master

MeFakeScientist · October 17, 2019

Hello all,

Thought I'd pop a post in here to get some opinions/thoughts on something I noticed with my system last night while fiddling about.

I want to stress that I don't have an actual problem I'm just curious/stupid.

So...

I thought I'd take a look at profiles in Ryzen Master (RM) as I noticed my CPU didn't seem to be doing much boosting during games etc, I wasn't noticing any performance issues but I thought why not have a quick look. The games I looked at were mainly GTA5 (when it works) XCOM2 (I know I'm at the cutting edge) and a selection of other games from different generes (FPS, strategy, minecraft etc). I wasn't sure about the CPU behaviour I saw in RM so I'll summarise it below.

With RM set to default mode (no profiles had previously been selected) the OC mode was set to 'default' although randomly it put itself in manual and I 100% didn't tell it to!

CPU speed in game: About 3.8 GHz on some cores, the other cores were between 250 MHz at 2 GHz

CPU Temp: 44 - 55 °C depending on game/what was going on etc.

With RM set to 'Creator Mode' OC mode set to PBO

CPU speed in game: Between 4.4 and 4.6 Ghz on some cores, other cores anywhere from 250 MHz to 3+ GHz

CPU Temp: 50 - 60 °C depending on game/what was going on etc.

Now, there is nothing inherently wrong with this behaviour I know, the CPU is boosting as per PBO and because of this is hotter than it was before. My question is considering that before I didn't notice any issues in games and the CPU wasn't boosting much/at all. So why is it choosing to boost now if the workload is the same/very similar? The CPU is also much less stable at idle than before with the random activity spikes and subsequent temp spikes being much more aggressive. Is this just a feature of PBO because it doesn't seem a very refined behaviour if the CPU takes a sledgehammer to every task when it may only need a light tap like when it's idling away.

I'd appreciate any thoughts or just general abuse over me not understanding how computers work!

For info my CPU is a 3900x, I have the latest BIOS, Chipset drivers etc.

Thanks!

Deli · October 17, 2019

I find the PBO/Auto Overclock a bit odd too. Sometimes it seems to improve performance a little. The other time no difference what so ever. And the CPU definitely runs hotter.

Depends on what I do. Sometimes I just run it stock/default, so it will be quiet and cool. When I do all core workload, like Handbrake, I'll just overclock it to 4.3GHz. Don't bother with the PBO/Auto overclock anymore.

Also a 3900X user.

MeFakeScientist · October 17, 2019

3 hours ago, Deli said:

I find the PBO/Auto Overclock a bit odd too. Sometimes it seems to improve performance a little. The other time no difference what so ever.

This is what I find the most odd, it seems as though the CPU does the same workload but in a much more up and down manner with regards to its clock speed.

I can't help feel like I'm missing something though, I know what PBO is supposed to do and I can see it doing it but I don't always know why and to what end!?

MeFakeScientist · October 17, 2019

I've got an image here from Ryzen master of the CPU in creator mode with PBO on, this is at the desktop, idsle and with nothing else running. It's obvious how spikey it is from the histograms. When PBO is off the temp is essentially a flat line and the speeds are much less spikey.