Ryzen 5 1500X + AB350M Pro4

This is slightly off topic, but since I'm planning to upgrade my GPU at some point, I decided to find out what sort of power headroom I have with my PSU. So, I went out and bought a plug power meter to measure my system's power consumption at the wall. When running in-place large FFTs with Prime95 (supposed to give the maximum CPU power consumption), the meter showed my system was drawing ~140 W. Running Superposition @ 1080p (windowed and maximum settings) alongside Prime95 raised the figure to ~260 W, which fits quite nicely with the 120W TDP of my GPU. Although this may not be the absolute maximum amount of power my system can draw from the wall, I doubt I'll see anything beyond this in normal use. On the other hand I should be prepared to see power consumption similar to this during gaming, since I saw consumption figures of up to ~240 W during Firestrike (the combined benchmark).

So, since my PSU can sustain 550W and since my PSU's +12V rail is rated at 45.8 A (~550 W), in principle I should be able to run any contemporary GPU without issues (if we disregard the fact that I would need to use a split cable instead of two separate cables). Even if I wanted to leave 100 W of "breathing room" for the PSU, I could still go for a ~300 W GPU, which includes anything up to a reference Vega 64.

Testing is still ongoing, but looks like 3.9 GHz requires more voltage than I'd like to use. However, 3.8 GHz was stable in Prime95 blend test for 8 hours @ 1.325 V - and with RAM speed increased to 3333 MHz! It seems that the lower temperatures and/or higher Vcore also help the IMC handle higher clockspeeds. I haven't touched the timings yet, but I might give that another try as well.

The maximum temperatures during the 8 hour Prime95 stress test were 68.5 C for the CPU and 49.5 C for the socket. Vcore (SVI2 TFN) sat mostly at 1.337 V under load, so a bit more than what was set in BIOS and still under the "safe" value.


Edited by PetrolHead - 21 Apr 2018 at 12:14am

I decided to upgrade my CPU cooler, and after some thought I decided to go with an AIO liquid cooler, namely Fractacl Design Celcius S24. Installation was relatively easy, but would have been even easier if the manual hadn't instructed to twist the Intel mount in the wrong direction to get it off. The end result is good regardless. There was no increase in noise levels*, yet max temps** in P95 blend test (after roughly 20 minutes) fell from 74.3 C to 61.8 C, and max temps in AIDA64 stress test (after the temperature plateaued) fell from 70.9 C to 59 C. Socket max temps fell from 54.5 C to 46.0 C and from 52.5 C to 44 C, respectively. There were some temperature spikes - up to 66.8C - during AIDA64 after the installation, but I'm not sure if these are just sensor glitches or if it's something related to running in the cooler. I saw no such spikes during Prime95 and the cooler seems quick to react to increases in load.

Overall, the drop in max temperature is maybe not the biggest, considering I was using the stock Wraith Spire cooler. On the other hand, the Wraith Spire is very capable for a stock cooler. Running the CPU fan at higher RPM could have resulted in even lower temperatures, but it would have also increased the noise. Another nice feature of the liquid cooler is that now hot air is blown directly out of the case (from the top). The airflow over the VRMs' heatsinks may not be as good as before, but what air flows through them should now be cooler.

All that's left to do now is to see if I can run higher clocks and voltages without the system becoming unstable.

*The cooler has two settings: "Auto" and "PWD". Since reviews saw no significant difference between the two, I'm running the cooler on "Auto".

**Temperatures from HWiNFO64.

It seems I was partially right about the CPU fan header after all, but the issue seems to be related to software, not hardware. The cooler spins at different rpms when I use silent, standard or performance mode, but the custom setting doesn't work. The fan spins at roughly the same rpm regardless of whether the CPU is under the 65% limit or over the 90% limit. I guess I'll have to wait and see if the next BIOS update will fix it.

3.7GHz @ 1.25V (1.280V) was stable for 8 hours in the standard Prime95 blend test. Max temps were 77C CPU and 57C socket.