I’ve tried doing some things, and it’s a struggle. For one thing, I can’t seem to be able to undervolt or underclock the CPU. Neither Ryzen Master nor the BIOS options ended up doing anything.Well, not completely nothing, the voltage did seem to take more time to read 1.4V and system power when running Prime95 was around 120W instead of 127W. But underclocking didn’t seem to do a thing and voltage tweaking didn’t seem to do any more than that. It’s not that the system was unstable or stopped working, it simply didn’t do a thing.
GPU undervolting did work, although only when I dropped the SOC voltage. But that made quite an obvious change, from around 88W in FurMark at 1.1V to around 82W at 1V. Still, without the ability of saving power by tweaking the CPU I felt that it was easiest to just use the 35W BIOS option.
Given that I had already tested that, I figured I’d move from power testing to something that was on my original test plan: comparing the integrate Vega 8 to the Radeon HD 5750 in my Phenom II PC.
I opened the old desktop, took out the 5750 and cleaned the dust with a compressor, put a 5550 in to replace it, and put it in the 2200G PC (the old PSU didn’t have a 6 pin PCIe power connector, but I have enough converter cables for that).
When powering the PC on, Windows was stuck in 1024×768 resolution. Windows update claimed that I have the latest drivers, apparently assuming that the Raven Ridge drivers should also work for the 5750.
What was worse was that after a few minutes the display turned off, and I couldn’t turn it back on. The PC still worked, and I was able to push the power button and it shut down. Upon rebooting I went to download Catalyst 15.7.1. The display stopped again so I wanted a few minutes in hope that the download will finish, then shut down and restarted.
I then started the driver installation, went away and returned to see the display went off again. After a restart Windows asked me to restart again, so I did, and after that I finally had a 1080p desktop running.
I ran the Metro benchmark, and it looked like it’s running considerably more slowly than the Vega 8. Which was a nice thing to know, that the Vega 8 is a real upgrade. My original plan was to compare the 5550, Vega 8 with 4GB and 5750. When I got 8GB, I had figured that if the Vega 8 with 2x4GB is faster than the 5750, then I’d make comparisons of the Vega 8 4GB, Vega 8 2x4GB and 5750.
Unfortunately the display shut down again and this time I had to force shutdown the PC. I left it at that for now.
Obviously I can’t go on with testing without solving this problem. I have no idea what’s causing this, so I will try a bunch of random stuff, like installing the latest driver from Windows Update, resetting all power tweaks, and playing with the Windows power options. The card did work without problem on the previous PC, and I think it’s quite important to make sure it works here. I might try the 5550, to make sure it’s not a power issue.
If and when I manage to solve this, I’ll go on with the planned benchmarks.