FX 8370: Please consider RAM, NB & HT LINK ratio while trying to maximize system OC.
FX 8370: Please consider RAM, NB & HT LINK ratio while trying to maximize system OC.
Hi, please confirm if these statements apply to an FX 8370:
1) NB Freq & HT Link Freq should match.
2) RAM Freq should be one-third of the NB Freq.
3) Maximum CPU core temperature is 62°C.
4) Maximum CPU socket temperature is 72°C.
5) Boosting single-core performance requires raising the NB Freq.
6) NB Voltage depends directly on CPU socket temperature.
Let me know if you need further clarification.
I don't believe so, what makes sense about that? Default on most mobos is HT LINK: 2600mhz. NB: 2200mhz.
Another point is, it doesn't necessarily have to be exactly one third of the RAM frequency, though it often does. I tried 1866mhz RAM with a 2400mhz frequency, which is pretty close to a third and it functioned well for me. If you're using 1600mhz RAM or less, you might keep the NB frequency at 2200mhz.
62c isn't the maximum, AMD just advises avoiding temperatures above 62c core (or package) for long periods to ensure CPU longevity. The CPU will reduce performance around 70c and could shut down if it can't manage the heat. AMD overdrive is recommended for better temperature monitoring on FX CPUs.
1) I don't think so, what is the reasoning behind that? Default on most mobos is HT LINK: 2600mhz. NB: 2200mhz.
2) I don't think it has to be strictly one third of ram frequency however it usually works out that way. I used 1866mhz ram with a NB freqency of 2400mhz, which is very close to a third. That worked fine for me. If using 1600mhz ram or lower I would leave NB frequency at 2200mhz.
3) 62c is not the max, AMD just recommends not going above 62c core temp (or package temp like HWmonitor calls it) for extended periods of time for longevity of the cpu. The CPU will throttle around 70c and eventually thermal shutdown if throttling cant control the temps. AMD overdrive is said to be the best for monitoring temps on FX cpu's, it uses thermal margins in that program you don't want o see temps get into the negatives.
4) I have heard 70-75c for max recommended socket temp.
5) I have heard that as well however my testing showed really no difference at all nor does it make logical sense to me that increasing NB frequency would improve single thread performance. I have also heard that doing a BLCK overclock is better for single thread performance, I tried that too if it is it was not apparent in any benchmarks I ran.
6) Not sure on this one I would think it would be directly tied to NB temps and maybe VRM temps. It might affect socket temps not sure, test it out.
Dunlop0078, thanks for the reply.
1) I have been reading extensively through all the miss matched threads that detail fx 8xxx OC's (most of them lead nowhere!) and have read lots of people stating that the system works best with the NB/HT Freq being the same. Was wondering if that's just an old wives tail or not!
Interestingly I cant get p95 blend stable with anything above 2600. (This is with a 4.0GHz clock) The max CPU/NB Voltage I am allowing is 1.3v - going higher than that induces an amber warning in BIOS (the figure turns Orange, increasing it above 1.35v turns it Red - I'm guessing thats a warning feature?) - because my socket temps are already hitting 72C.
2) I see. This is another bullet point I devised after trolling through the other threads - It was mentioned a time or two and I got the impression the author knew their stuff.
3 & 4) Thanks for clarifictaion. I'll gauge this as 24/7 usage versus P95 torture and find a happy medium.
5) Again, thanks for the clarification. As, I mentioned above. I cant get it stable above 2600 anyway so I guess that's no longer a thing for me, 2600 it shall be!
6) Ah Okay, I think I understand now. I was - probably, stupidly - under the assumption that socket temps were the VRM temps! Wouldn't it be a good idea to monitor VRM temps directly? They get waaaaay hot on my Asus M5A99FX Pro 2.0. Even with a ghetto fan array blowing air directly onto the heatsinks!
Concerning number 6, it would indeed be beneficial to keep an eye on VRM temperatures. I own the M5A99X EVO, which shares the same VRM configuration as your motherboard, and it uses a 6+2 phase design. My previous model lacked a VRM temperature sensor, so without adding your own thermal probe, I can't accurately measure those temps. Most VRMs are built to handle up to 125°C, but they still get quite warm during heavy use. It's wise to implement active cooling on the VRM when pushing high-end graphics cards, as I did by attaching an 80mm fan directly over it. I've run a 4.9GHz 1.39V setup on an 8350 for five years without any problems—it still functions perfectly now.
Personally, I often exceed the recommended overclock limits during stress tests like prime95. If the system remains stable and cool enough in games or other workloads, I consider it acceptable.
For those not using it, I recommend installing prime95 version 26.6 on FX CPUs, as it doesn't include AVX instructions. Adding AVX would significantly increase heat and processing demands, which isn't ideal for tasks that don't leverage it.
I understand your point. It’s better to focus on practical stress if daily tasks don’t hit those levels. I think my main CPU workload is probably rendering videos. I haven’t done one in a while, but I’ll keep an eye on it when I do. Maybe I’ll set up a separate, more stable OC profile for such tasks. Now that I have the profiles, it’s helpful. 😀
Thanks for the advice about the P95 version. I didn’t know about that.
My fan setup has a 120-logged unit between the CPU cooler and I/O. It puts a lot of heat on the VRM heatsink. I also connected an 80mm fan to sit on the (South Bridge) heatsink, which is linked to the VRM by a pipe. That definitely made a difference. The area in the case that matched the VRM was getting very hot before.
Thanks again for all the support. Appreciate it.
P.S. I checked the XMP settings for RAM last night and recreated my OC using the DOHC setting, picking the most aggressive profile. So far everything looks good.