Ryzen 3900X thread

Steedie · 11 Aug 2019 at 10:54

Posted in the Zen 2 thread but worth mentioning here too.

Had some good results undervolting my 3900X. Experimented with the negative offset in 0.025 increments all the way down to 0.125. Best results were at -0.1. Saw a 100 point boost in Cinebench and 5fps average increase in the Shadow of the Tomb Raider benchmarks.

Best for me though was a big drop in load temps. Was previously hitting as high as 85 under a Cinebench run, but now the highest I’ve seen is 77 where 75 seems to be the norm.

esoteric · 11 Aug 2019 at 11:33

My overall experience at the moment from moving from an I7 930 to a 3900X. Before UserBenchmark changed the 3900X was a 150% upgrade in effective speed. Now it's a 112% effective speed upgrade.

Here is the page currently - https://cpu.userbenchmark.com/Compare/Intel-Core-i7-930-vs-AMD-Ryzen-9-3900X/m79vs4044

I don't remember what the single core improvement was but now it's 92% which is still absolutely huge.

I had three games in mind to test before and after the CPU change, Monster Hunter: World, BATTLETECH and Rocket League. I play at 1440p 144Hz if I can on a 970. In MHW I would be 40-55 FPS, BATTLETECH I would be around 40-50 and Rocket League 120-142. I set 142 as max FPS to keep GSYNC stable. After the 3900X nothing has changed so I'm GPU bound at 1440p, I knew that anyway but not by how much.

Dropping the resolution to 1080p now I can see how much of an improvement my CPU is making. Before and after in MHW is 35-50 to 60-80. BATTLETECH was 40-50 to 90+.

Next year I'll have to get Ampere based GPU.

Ross Thomson · 11 Aug 2019 at 16:15

esoteric said:
Before UserBenchmark changed the 3900X was a 150% upgrade in effective speed. Now it's a 112% effective speed upgrade.

one of the most pointless databases to use to compare CPU's

kitfit1 · 11 Aug 2019 at 16:50

Ross Thomson said:
one of the most pointless databases to use to compare CPU's

Apparently not if you are Intel and in desperation need to show your cpu's as best you can.....................................just bribe the developers.........................worked in the past and obviously still does.

roysters · 11 Aug 2019 at 19:56

Tried two different CPU blocks. 3900x with a 2080ti in the loop still gets to 75c in CB R20.

Idle about 35c. Gaming (overwatch about 50 - 55c)

Least the 2080ti us super cool and 35 - 40c!

Everything on default apart from XMP and manually put 3200 8pack ram to 3600 which runs fine

VincentHanna · 11 Aug 2019 at 20:23

I know it's a bit older, but I tried ROG Realbench to stress test.

After 5 mins my CPU got to 82°C, which seems quite high considering I have an AIO with 360 radiator.

Does anyone mind running a comparison? http://dlcdnmkt.asus.com/rog/RealBench_v2.56.zip

Maybe I need to re-seat the cooler.

roysters · 11 Aug 2019 at 20:25

I'll try in a bit.

roysters · 11 Aug 2019 at 21:27

Ok done the 15 min stress test. 61c max after 15 mins

VincentHanna · 11 Aug 2019 at 21:30

Cheers. Mine clearly isn't performing correctly then.

Donnie Fisher · 12 Aug 2019 at 07:43

Or your cooling isn't ....

VincentHanna · 12 Aug 2019 at 10:03

VincentHanna said:
Maybe I need to re-seat the cooler.

VincentHanna said:
Cheers. Mine clearly isn't performing correctly then.

That's what I meant, my AIO.

robfosters · 12 Aug 2019 at 12:56

VincentHanna said:
That's what I meant, my AIO.

Mines hitting 82 as well, but averaging 75-77. I'm using a Corsair H100i AIO cooler and I'm sure it's installed properly. Steedie's hitting high 70's-80's too.

I'm a little suspicious of the 61 result. I can only imagine it hitting that under 100% load if undervolted and cooled with a custom loop. Can't imagine any standard air or AIO cooler keeping it that cool.

VincentHanna · 12 Aug 2019 at 12:59

Oh that makes me feel better then.

Mine idles at around 52, with the occasional spike and was generally in the 70's for gaming.

VincentHanna · 12 Aug 2019 at 13:27

Someone on Reddit also said:

I have a 3900x on an Asus C8H with a Corsair H115i AIO. I currently have all cores clocked at 4.25GHz with 1.28v and as soon as I start running Prime95 small FFT my temps jump to the mid/high 90s. Seems odd with such a low voltage and 280mm AIO. I've reapplied MX-4 thermal paste a couple times with no difference. Is Prime95 (v29.8 build 5) not usable with Ryzen 3000 because of the 7nm density and chiplet design?

Realbench and AIDA64 run with the CPU < 82C for an hour.

robfosters · 12 Aug 2019 at 13:50

VincentHanna said:
Someone on Reddit also said:

I have a 3900x on an Asus C8H with a Corsair H115i AIO. I currently have all cores clocked at 4.25GHz with 1.28v and as soon as I start running Prime95 small FFT my temps jump to the mid/high 90s. Seems odd with such a low voltage and 280mm AIO. I've reapplied MX-4 thermal paste a couple times with no difference. Is Prime95 (v29.8 build 5) not usable with Ryzen 3000 because of the 7nm density and chiplet design?

Realbench and AIDA64 run with the CPU < 82C for an hour.

Well that guy either has a very broken cooler, CPU or both. I've just run P95 small FFT for 10 minutes and didn't get above 74 degrees.

AStaley · 12 Aug 2019 at 14:06

I have an Asus AIO with 360 rad and running P95 for 30mins I get around low 80's if i use a silent fan profile.

Illuminist · 12 Aug 2019 at 14:46

VincentHanna said:
Someone on Reddit also said:

I have a 3900x on an Asus C8H with a Corsair H115i AIO. I currently have all cores clocked at 4.25GHz with 1.28v and as soon as I start running Prime95 small FFT my temps jump to the mid/high 90s. Seems odd with such a low voltage and 280mm AIO. I've reapplied MX-4 thermal paste a couple times with no difference. Is Prime95 (v29.8 build 5) not usable with Ryzen 3000 because of the 7nm density and chiplet design?

Realbench and AIDA64 run with the CPU < 82C for an hour.

robfosters said:
Well that guy either has a very broken cooler, CPU or both. I've just run P95 small FFT for 10 minutes and didn't get above 74 degrees.

AStaley said:
I have an Asus AIO with 360 rad and running P95 for 30mins I get around low 80's if i use a silent fan profile.

Do you both have all core manual overclocks as well?

VincentHanna · 12 Aug 2019 at 14:52

Nope, stock boosts.

Only thing I changed in the BIOS was to set the memory to 16-16-16-36 3600 1.35V

robfosters · 12 Aug 2019 at 14:53

Same for me. Running at stock with XMP1 selected in BIOS.

Illuminist · 12 Aug 2019 at 15:28

VincentHanna said:
Nope, stock boosts.

Only thing I changed in the BIOS was to set the memory to 16-16-16-36 3600 1.35V

robfosters said:
Same for me. Running at stock with XMP1 selected in BIOS.

This is why his temp is so high and yours is not, I also peak at 80+on cinebench at 4.3 all core clock. I can't run intel burn, or prime 95 as it would get to 97.c, the 3900x is too much in too small a place to be cooled by conventional cpu blocks, they just aren't made to deal with 12 core in a 7nm package running at 4.+ manual all core oc