I have had my 8350 OC'd to 4.65 GHz with a multi of 18, bclk of 2.57 and Core V of 1.40 and I seem to be at the limit of my NH-D14 cooler. I was trying to find some more info on OCing with turbo enabled to help boost the weak single core performance of the FX CPUs. Computer Restore's guide on overclock.net was the first time I saw this sort of OC mentioned. http://www.overclock.net/t/1348623/amd-bulldozer-and-piledriver-overclocking-guide-asus-motherboard#
Unless I missed it when I read through the thread, I didn't see any real way to test the stability of the Turbo OC or any real steps to it either. I understand that the Turbo frequency can be changed with the bclk as the multi is locked at 20.5 for Turbo iirc. But then to test it should I just be running Prime95 or OCCT with only one thread? Or try to disable 3 modules and then run the standard OC stability tests as it will still turbo with 2 cores but just not to the full 20.5 multi?
I guess any information and help I can get would be much appreciated. If nothing else I guess I play the try shit till it works method.
Turn turbo off, it's not worth the potential instability risks. I've fooled around extensively with the FX-8350 with trying to get an overclock with turbo still enabled and it always leaves me with a lower overall OC than what you can reach without turbo enabled. Single vs multi-thread performance has little to do with multiplier and base clock, its all in the CPU architecture. I wouldn't bother trying to chase a high multiplier with an FX-8350 as they overclock better with the bus clock if you keep your RAM/NB/HT dividers correct. Granted, you can still get a decent 4.6-4.7GHz overclock with the FX-8350 and still use your power saving features. That is something to remember if you aren't chasing 5 GHz or more.
i have an FX8300 OC-ed with turbo at 5.0ghz and with all cores at 4.4....
the way I tested it(not saying it is good or bad) is just ocing without turbo towards how much i want mu turbo to be and then i made those settings as my turbo and started checking with occt on 2 cores and started decreasing in voltage until it got unstable then i bumped it up a bit....although it behaves a bit weird it still somehow works...(it depends on how much load the processor is on..it can get from 5.0 to anything between 4.4 but not lower...so not only 2 states...there are at least 7)
there is a program that i use to overclock it ..something called amd tweaker if i am not mistaken...i am not at home right now..maybe i'll check when i get home and come back with a definite answer...
EDIT: it is called AmdMsrTweaker_1.1 so check it out
i don't use this oc profile all the time because i do not really need it...i did it only for fun and because many people said it won't work so i had to try...it works and you can use it but i don't really see the reason other than "yea i got my cpu to 5ghz" even at stock 3.3 it's enough for me
Thanks for the reply guys.
@Batojiri I think it would be cool to hit the "magical" 5 GHz but I don't plan on it with my current set up as it seems pretty close to maxed out. I was really just kinda curious how to do this type of OC for fun. Ill have to try giving just a base clock OC a go this weekend and see if I can get it a bit higher.
@Casian_Filigean thanks for the walk through of how you did it. That was about the only way I could think of to test it but wasn't sure if I was missing something else. And I kinda want to do it for the same reason you did with the "it won't work, don't bother" motivating me lol.
Ill check out AmdMsrTweaker and report back in with my findings so the next person looking might have something else to compare to
@Zer0Log1c1 hope it works out for you..let's see if u won the lottery and can push that thing over 5Ghz...waiting on those updates
Alright, so I can completely understand why most people strongly urge against OCing without disabling Turbo. This has been a learning experience to say the least.
So far I brought my system from a 4.65 GHz OC with the bus at 258 and V Core at 1.404 to a Turbo OC maxing at 4.67 GHz and bottoming at 4.4 GHz. I have not used AmdMsrTweaker as of yet because I was curious to see how far I could go with the stock Turbo settings. Now I know I've read all over the place that the multi for the highest Turbo setting is 20.5 by default and that's for only two cores. My system seemed to have no problem at all turboing up to that 20.5 multi (4.67 GHz) when running 8 Prime95 threads. None of the cores stuck at that speed for extended periods of time but according to HWiNFO64 the cores averaged out at around 4.57 after about 20 mins.
I am very far from finished since it took close to 4 hours just to get my 8350 to cooperate with the Turbo on and having a higher base clock and/or multi. I still need to so some longer duration stability tests and try for some higher clocks but idk how much time I'll have before this coming weekend to play with it.
So some things I've learned so far:
It almost seems the 8350 won't turbo if some of the power saving features aren't on (I need to test this a lot more still, might have been a fluke). After turning all of them back on and booting in my CPU would turbo again.
Changing the Turbo multi in my BIOS does not stick when I load into windows and it still turbos to the 20.5 multi
Setting my base multi higher than 19 would mean that my CPU would down clock to 19 at times so a BCLK OC seems to be the only way to go
Running all 8 threads in P95 would occasionally drop my multi down to 7, I'm guessing because it was getting close to the top of the thermal envelope but temps were safe at 52C on the socket and <48C at the core. I want to see if disabling some of the power saving features can take care of this
So no final outcome as of yet, but this has been one hell of a fun project so far, in a challenging sorta way. I'll try to keep updating as often as I can. I think the goal will be a base clock of 4.6 or 4.7 with a turbo of 4.9 or 5.0
Edit: I almost forgot I haven't listed my rig anywhere...
CPU- FX 8350 (obviously)
Mobo- Asus M5A99FX R2.0
Cooler- Noctua NH-D14 with stock NF-P12 and NF-F12 ippc 3000 (second ippc 3000 died)
RAM- 16 GB Kingston HyperX 1866 MHz 4 Dimms
GPU- Sapphire Vapor-X 280X
PSU- Corsair HX650
Storage- 250 GB Samsung Evo, 240 GB OCZ Arc 100, 240 GB OCZ Vector 180 and 1 TB WD Blue
Case- Antec Eleven Hundred V2
OS- Win 10
I remember when I tried to experiment with Overclocking with Turbo a while ago. The idea was that if games only use a few threads, why not have the computer really boost up the one or two cores in use, then return to my base overclock when in general use? Sadly, BIOS settings did not really allow for too much control, and while the AMD Overdrive settings did allow for options, they never really seemed to work like I wanted.
If you can somehow get it to work like that, that would be quite interesting.
I have been experimenting, in a minor way, with Northbridge overclocking on the FM2+ platform. The performance boost is minor, but there. I have been thinking of doing a similar write-up on it.
Sorry for the delay guys, been really busy with work and school lately leaving less time for overclocking.
@Calculatron That was my thought process too. I had just picked up Arma 3 on the latest steam sale and it looked like it was only heavily using two threads to me. So like you said, turbo up for the game and then lower clocks for everything else.
Even with AmdMsrTweaker my voltage keeps dropping to .9 and to OC with the voltage offset puts my turbo voltage up to 1.46 just to get the low value to 1.1 volts-ish. I've been trying to just up the min volts for vCore since its when that drops my system will hang in stressing.
I was able to run P95 for 3 hrs with only 6 threads running but that's not the full system load. This set up is really finicky to test it seems. I might just test again for 6 threads and reboot with my standard 4.6GHz for any stressful or important work.