I just read an Overclocking guide from AMD telling me that my CPU NB should be double what my ram is set for. That would mean a CPU NB clock at 3732mhz for 1866mhz RAM and I don't even want to try that lol. So is my RAM being extremely bottlenecked by my memory controller? Being that it doesn't go higher then around 2600mhz I believe. And does this mean that anything over 1333 is usless in FX based machines? And would i be better off just lowering the timings on the ram while setting a lower clock speed?
If you have an FX processor you need to have the CPU/NB as much or just above your rated RAM speed. Those recommendations you have been reading are for Thuban based processors.
Thuban was the phenoms right? That link was for the FX line. Or is it just bullshit? It says:
CPU NB FID: CPU NB Clock Multiplier. Determines the CPU NB frequency. In the case of the AMD FX-8150 CPU, the default value is x11 (11x200MHz = 2200MHz). CPU NB Multiplier adjustment requires a reboot (it can not be adjusted on the fly). Can be adjusted in steps of x1. Note that CPU NB clock should be 2x Memory clock or higher (e.g. DDR3-2400 (1200MHz) would require at least 2400MHz CPU NB clock). CPU NB Multiplier is unlocked on all of the AMD FX-series CPUs.
I just changed my RAM to 1333mhz from 1866mhz and my fps accually went up a hair. (only by 1fps).
2200 MHz is the standard Memory controller frequency and is fine for operating any RAM up to speeds of 2200 MHz. The only reason why you would want to overclock it between 2400-2600 MHz is to run 2400 MHz RAM or get an effective memory overclock without actually changing the clock frequency of your RAM.
I would take what other people say about overclocking FX processors with a grain of salt on forums such as tomshardware or overclock.net as I've done extensive research into many of the overclocking options given by many of the different forums. Some of the claims are just downright incorrect. Phenom processors were better memory controller overclockers than the FX series processors. With the Phenoms, they were only technically supposed to support DDR3 1333 MHz. Overclocking the memory controller allowed people to get DDR3 1866 MHz running on a Thuban based core.
Is as simple as I misunderstood the memory clock with the memory frequency? so 1866mhz would be a clock of 933 with a multiplier of 2? and the CPU NB freq should be over +1866mhz because its double or over double the 933? That makes more sence. -_- hence why it says 9.33.... bare with me while i make sence of this lol.
Yes
But it doesnt explain why in my bios it says "warning if the cpu nb freq. is lower then the ht link the freq will be adjusted by default." it doesnt say which frequency will be adjusted but why would the default settings cause this problem? Should i lower the ht link manually to 2200mhz from 2600mhz?
its a 990fxa-ud3 with an 8120 and 2x8gb 1866 if it matters.
HTcannot outrun the NB (Rule) Try uping the voltage a bit
So ur saying raise the CPU NB to match the HT Link?
I usually keep it lower but close to ht do not ever going over, a higher nb will increase temprtures on your cpu but at the same time make it more stable.
In order to do this you need more V most people say 1.3 is ample and i run with that rule
Drop the HT link to match your CPU/NB frequency.
Im running a corsair h110 cooler with 2 noctua 140mm flx fans do you think its a bad idea to go to 2600 with both clocks? scratch that... with both frequencies? lol
When its not stupidly hot outside and im gaming (most of the winter) The cpu is at 4.5 ghz and its never seen over 50c according to hardware monitor anyway. and the thermal probes on my fan controller agree although they are just packed in by the water block.
I'll be much clearer, for example you would want your nb to be 2600mhz and ht 2200mhz not the other way around you can drop your ht down more but it will affect the VGA performance.
(these specs do not apply to your caase just an example)
lol because the stock settings are the exact opposite, I even just cleared the cmos and loaded optimized settings and it puts it at 2200mhz cpu nb and 2600mhz ht link and gives me the warning. lol thanks for clearing that up ill fix those stupid stock settings.
You can run both frequencies at 2600 MHz just you cant have the HT frequency higher than the CPU/NB frequency, it doesnt help anything to have it set higher than your CPU/NB frequency.
Let us know how it goes
I killed it going to cpu nb 2600mhz on stock clock, worked like a charm at 1.3v though. So at cpu-3.6ghz ram-1866mhz 9-10-9-27 cinebench scored 5.86 at cpu nb-2200mhz and 5.92 at cpu nb-2600mhz ill post back with the 4.5ghz score. It was 7.37 at 2200mhz if i remember right...
That sounds right as changing the multiplier for the Memory controller overclocks the ram without changing the actual RAM speed itself. Just make sure the RAM is stable with the timings you have it set at with the Memory controller overclocked, if you start getting errors you need to loosen up the timings on the RAM or drop the memory controller frequency.
For perspective I've got my FX-8350 set to 4670 MHz with a 266.9 MHz bus x17.5 multiplier 2400 MHz CPU/NB and 2400 MHz HT link with 4x4GB of DDR3 2133 MHz ram running at 11,11,11,33,44, 3.9ms, 1T
I found that changing the fsb lowered benchmark scores and when I only changed the multiplier things ran way smoother and scored the highest. Ive brought er to 4.7ghz but i found the benchmarks for bulldozer peaked at 4.5ghz and then started dropping off. Probably chip specific I guess.
Anyway at 4.5ghz 1.4125v and the cpu nb at 2600mhz 1.3v it wouldnt boot. At 2400mhz it booted and scored 7.35 on cinebench and at 2200mhz it scored 7.39 my highest yet makes me wanna try 2000mhz, but I know cinebench isn't everything.
And incase your wondering that 1.4124v cpu core was the cinebench score peak.
That's not bad at all Mine scores a 7.85 with the settings i mentioned in that post above. but then again I have a Vishera and yours is a Bulldozer with slightly slower RAM. I need to run my CPU at 1.440v however as I've recieved one of the lower teir pieces of silicon that didn't make it into the running for becoming a FX-9590. Doesn't matter though, the way this thing is setup right now is just bad-ass. I'm able to keep my power saving features on and my CPU idles at 1868 MHz. This PC pulls a lot less power at idle then the neigh sayers want you to believe.