FX 8370: Advice please regards RAM, NB & HT LINK ratio when attempting max system OC

[introaether]

Hi, I have some questions before I proceed any furter with my system OC. If you know the answers, I'd appreciate your reply.

Is the following true for an FX 8370?

1) The NB Freq & HT Link Freq should be the same.

2) The RAM Freq should be 1/3 of the NB Freq.

3) Max CPU Core temp is 62C

4) Max CPU Socket temp is 72C

5) To increase Single core performance you need to increase the NB Freq

6) NB Voltage is directly tied to CPU Socket temp

Thank you, peace.

 

[Dunlop0078]

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.

 

[introaether]

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!

 

[Dunlop0078]

Regarding number 6. Yes it would be a good idea to monitor VRM temps, I had the M5A99X EVO which uses the same VRM as your mobo I believe, 6+2 phase. Mine did not have a VRM temp sensor, so short of installing your own thermal probe there is no way to know the VRM temps on that mobo. Most VRMs can withstand up to 125c so they can get quite hot without damage, however it is a good idea to have some active cooling on the VRM when OCing FX chips, I just zip tied a 80mm fan over the VRM blowing air down on it. I ran 4.9ghz 1.39v I think on an 8350 for 5 years with no issues, it still works today.

I personally always pushed my overclocks past what I could run stable in stress tests like prime95. If it was stable and cool enough in games or other tasks I actually use the computer for then that's fine with me.

I would use prime95 version 26.6 on FX CPU's if you aren't already, it has no AVX instructions. AVX adds an unrealistic amount of heat and load to a CPU that is going to be used for say gaming or other tasks that don't utilize AVX.

 

[introaether]

Yeah, I agree with you. Why worry about unrealistic stress stability if everyday use isnt getting anything close to it. I would imagine the hardest task my CPU has to do is render videos. Havent done one for a while, but will be sure to monitor things when i do. It might be I create a seperate, more stable OC profile for such task. Now that I have profiles

Thanks for the tip regards P95 version. I wasn't aware of that.

My ghetto fan array consistes of a 120 lodged between CPU cooler and I/O. This blows onto the VRM heatsink a treat. I also wired in a 80mm to sit on the (South Bridge) heatsink? The one which is joined to the VRM heatsink by pipe. I has definately helped. The case area that aligns with the VRM was scorching before.

Again, cheers for all the help. Greatly appreciated.

Ps. Looked into XMP settings for the RAM last night and recreated my OC using the DOHC setting, choosing the most aggresive RAM profile. Seems all good so far. Laters!