AMD FX 8370 overclocking: a possible speed limit problem
AMD FX 8370 overclocking: a possible speed limit problem
So I've been experimenting with a multiplier overclock on my CPU, the idea was to squeeze some extra performance out for VR until next gen hits and an upgrade is necessary. I managed to disable all the bios stuff that was blocking me (like powernow etc), enabled custom p states and HPC, put it at 4.5Ghz and got it fairly stable. The big issue is that when under load, it performs as expected most of the time, but it also regularly drops down to 1.4Ghz for a second or 2 before jumping back up. After testing until 3am last night, I found this was the cause of the significant regular performance dips I've been having in VR, and that my performance is actually better on stock settings without these weird CPU spikes. The overclocked performance is significantly better when it doesn't throttle however, so there is a gain to be made if I can stop the core speed dropping. What I'm trying to figure out is what the hell is going on. My PSU is overkill, and I have a Gamaxx 400 cooler, so I have a suspicion that maybe its VRM throttling (as the CPU never exceeds 57 degrees C and even then it normally maxes out at 52, well below max operating temps). How I can actually verify that I have no idea though. I've only overclocked one CPU before and didn't run into this, can anyone help? EVGA Supernova 850W Semi Modular 80+ Bronze Power Supply AMD FX 8370 Black Edition 4GHz Socket AM3+ 8MB L3 Cache + Gammaxx 400 Asus GTX 1060 TURBO 6GB GDDR5 Graphics Card Biostar TA970 Plus Ver. 5.x Socket AM3+ 8-Channel motherboard 3 HDDs 2 SSDs
That motherboard seems to have a 4+1 VRM setup, which is pretty weak. It does have a heatspreader that makes it slightly better than some others, but it's definitely not great for overclocking a 125-watt CPU. I'm pretty sure the VRMs are causing the issue.
Thanks for letting me in on your suspicions. How did you find that out? I checked my site looking for a mobo but don't think they talk about VRMs at all. Do you say I shouldn't overclock at all, or just be careful with it? I'm trying to see if 4.2Ghz (100mhz above boost) can handle anything over stock and slowly raise from there. That would have been better the first time around.
I read a review that said this card had 5 phases, so I thought maybe they meant 4 plus one. How much power you give it depends on how bad an issue would be if the motherboard breaks down. Even though there is some protection built in from the posts online, lots of people have come to my help when their cheap motherboards fail over and over again.
Yeah, well, that old moba was super cheap. If it breaks, I can just say hey, let me get one with better VRMs instead. Anyway, I'm planning on building a new rig in the next year or two, so I know I need an AM4 board anyway. I tested this thing this morning and 4.3GHz feels really stable even when stress is applied, without any throttling or extra power needed. Going higher to 4.4GHz or above requires more voltage, which seems likely to cause random crashes or slow-downs, so I'm sticking with 4.3 for now and calling it a big win! One last question: what number of VRM phases and setup would you look for if you want serious performance but not crazy LN2 overclocking? Just something solid that works well with air cooling.
Oh wow, now you don't even need to buy new AM3+ boards? I saw someone suggest a Gigabyte GA-970A-UD3P ATX AM3+ because of its 8+2 phase power delivery, but I can't find any stock for it. Guess I'll have to check used motherboards (I never thought about that) when/if this one runs out. Thanks for your help!
AM3+ stopped being made a long time back, around the same time as AM4 came out.