Here are my core system specs first:
Ryzen 2700X
Asus Crosshair Hero VII
2x8GB G.Skill FlareX 3200 CL14
EVGA GeForce GTX 1070 FTW3
Corsair H100iV2 with Noctua NF-F12 iPPC 2000 fans in push+pull config
Seasonic Prime Titanium 750w
I'm seeing a strange behavior that I just noticed recently when applying my memory overclock. Since I've had my 2700x (about 14 months) I just ran my memory overclock according to DRAM calculator (picture of Ryzen Timing Checker attached) and set Performance Enhancement to level 2 in the Asus BIOS and called it a day.
Recently, I've decided to try to get some extra performance and attempt an all-core overclock since my 2700X runs around 3.8-3.9Ghz with an all core load. Such as Rainbow Six Siege + OBS stream or Folding@Home. I wanted to get at least 4.1Ghz all-core since I am almost always running fully loaded which, again, puts me around 3.8Ghz.
So, I load into BIOS, load optimized defaults, and then start pushing clocks. I found that 4.15Ghz puts me in a good place in terms of voltage (1.3375v) and actually lowered my CPU temps significantly (warning sign that I notice later). During the OCCT burn-in test I noted ~100-110w total CPU package power.
Ok. I got my CPU OC dialed in. Time to put my memory OC back in. As you can see in the attached pic, my memory/memory controller can handle 3533 CL14 with fast sub timings + GDM on. The SOC voltage is 1.0125v, by the way.
Time to stress test with both a CPU OC and memory OC. I load up OCCT, run the same test and.....185w CPU package power!!!!
Within 2 minutes my system crashes.
Ok. I know faster memory and tight timings increases CPU performance at the same clock speed. More performance and a faster Infinity Fabric requires more power, but...70-80% more power?
I revert back to my previous config, 3533CL14 + fast subs and PE2. I run the same OCCT stress test and, sure enough, the power usage is high. About 160w even though the CPU is running around 3.85Ghz. My CPU temps are about 17*C higher even though the clock speed is 300Mhz slower and the reported CPU voltage is lower.
I load the 4.15Ghz all-core OC + memory OC again and start to dial back the clocks. Hoping that I can manage some sort of all-core performance boost. Nope. I am under 4Ghz before I am stable, almost entirely defeating the purpose of this exercise.
Has anyone else seen this behavior before? Is this something with Ryzen+ and IF? Maybe this is an Asus CH7 behavior?