AMD Overclock question

[sirpatch]

Hello people, first off allow me to introduce myself, My name is Nuno, and im new to OCF, but so far so good eh
Well, i have an AMD Athlon II X4 645 3.1ghz, and i was twinkering with the bios to get a stable overclock, and managed to get 3.7ghz (have to alter the FSB, the Multiplier is not upwardly unlocked), and HT is at 1995mhz, since i had to change its multiplier to keep it around 2000mhz.
I changed the FSB to 285 on the CPU, and the multiplier to 13x; whilst the HT multiplier is at 7x, so 285*7=1995mhz
I also tweaked ram settings, set the timings, voltage, etc and it runs on prime95 for 20 minutes without errors ( i know thats not a lot )
I have the voltage set at 1.47v, and i dont get bluescreens, prime 95 runs, but should i give it just another step forward on the voltage? Strangely, after formatting my pc, and doing this OC (i had an unstable OC previoulsy at 3.6ghz), rendered me a lot less FPS's than before on BF3, used to have 40-50 on Ultra, now i have 20-35 Previously, on the unstable OC, voltage was set on Auto
I have a cooler master V6 GT, which keeps my CPU idling during summer at 30ºC, and under full load prime95 at 47ºC, for winter temperatures, it goes around 6ºC Lower. The System Temperature is always 40ºC or so, winter or summer. (According to aisuite)
I have an Asus GTX 550 Ti overclocked by me, 1.15v 1080mhz Core clock, 2160mhz shader clock, 2380mhz memory clock, runs stable with kombustor and wont go over 57ºC
My question is, and probably a very dumb one, Having the multiplier at 13x, to achieve 3.7GHZ, doesnt give me a lower performance, than a 15x, with which the FSB would have to be 246, right? 3.7Ghz with a 13x multiplier doesnt give lower performance in games than 3.7Ghz with 15x multiplier?
I prefer 13x multiplier beacuse with it i can keep a better FSBRAM ratio, its at 3:8 atm
I set the RAM timings, voltage, but the DRAm frequency has to be auto, if i set it manually to 800mhz it wont load up, but to 667mhz it works, and its actually very close to 800mhz.! With Auto its at 760mhz according to GPU-Z, which, being DDR, is close to 1600mhz which is my ram speed, i know the difference is nearly none but that leaves me curious.
Anyways thanks in advance for your help

 

[boucher91]

it would help to have more info about you hardware such as my sig below,
also would need screenshots of cpu-z and hardware monitor..
sounds as your mem needs a slight volt boost and possibly the nb..
but cant really say without more known variables...

 

[trents]

Please run CPU-z and attach pics of these tabs: "CPU", "Memory" and "SPD". That will give us loads of info about your system and its settings in a snapshot. Shouldn't matter, by the way, if your CPU is overclocked via the multiplier or the fsb. It's the end product core frequency that counts.

What's your CPUNB frequency running at. Try setting it to 2600 and give the CPUNB a voltage increase to about 1.25 to support that. Works just like the HT Link frequency adjustment, a multiplier change. The CPUNB is part of the integrated memory controller and raising the frequency benefits memory performance.

When you have made several more posts you will have access to the "Sig" feature in "Quick Links" at the top of the page: "Edit Sig". Please do that soon.

 

[sirpatch]

Hello
No problem bout my rig
AMD Athlon II X4 645
Corsair Vengeance LP 1.5v 9-9-9-24 8GB RAM 1600mhz
Asus nvidia GTX 550 Ti DC
Cooler Masetr V6 GT
Asus M4A78LT-M
the NB voltage is set manually to 1.2volts.
EDIT: just checked bios settings, here they are for you:
Microcode updation disabled
secure virtual machine mode disabled
C1E anmd cool n quiet disabled
Advanced clock calibration disabled
VDDNB 1.2V
Loadline calibration: auto (51%)
HT link speed auto
HT link width auto
HT over voltage auto
Memory clock mode auto ( for the reasons mentioned in the first post )
Dram timings set manually according to corsair's indication,
ram volt: 1.5v, according to corsair's indication
Chipset overvoltage:auto

 

[trents]

Compare the frequency and timings of your current settings (Memory tab of CPU-z) with the XMP settings in the "SPD" tab. Your will see that your current frequency exceeds the rating of the ram and your CR is set to 1T and it should be set to 2T. Although, I am having trouble making out the values in your screen capture because the images are too small so I may be wrong about the frequency. It looks like you are currently running it at 780 mhz. Are my eyes deceiving me? Pleas crop the pictures first. Snipping Tool in Windows Accessories is great for this.

 

[sirpatch]

You can click the images to see full size
I dont get what you mean by exceeds the rating of the ram sorry, and how can i set my CR to 2T?, and i have to go set my trc to 41 right?
Also bout my NB frequency and voltage, and CPU voltage, what should i change? should i crank up the NB frequency and voltage and to what? And would that help me restore my performance on BF3, because with my unstable OC which crashed my pc all the time, i could get around 50 FPS average on BF3, maybe 40-50, now i get 20-35 or so after formatting pc and getting stable OC

 

[sirpatch]

Sorry for doublepost/bump,
I have a question, id like to keep this related to the OP but a little offtopic
whilst AI suite indicates:
CPU temp 32ºC
System temp 43ºC
Sisoft Sandra indicates
Board temperature 33ºC
CPU temperature 19.50ºC

Which one is right?
EDIT: on my bios there is no option to change ram command rate
EDIT 2: I increased ram voltage 1 step, so its 1.5xx volts, i relaxed the timings to CL10, 10-10-10-27, NB voltage is 1.25 volts,
still not very stable on Prime95 with lots of ram tested!

 

[trents]

CPU-z reports the memory speed at the bus frequency, not the DDRx transfer rate. The DDR3 transfer rate is twice what the bus frequency is. So if CPU-z reports the memory frequency as 760 mhz that's the equivalent of DDR3 1520 mhz and your ram is only rated for DDR3 1333 mhz.

You're probably wondering, "How did the memory frequency get that high?" It's because it's tuned to the front side bus. When you overclock with the front side bus the memory frequency climbs in concert with the FSB. So he trick is to start the memory at a lower speed than its rated for so that as you overclock it stays within a range that prevents it from becoming a source of instability.

You should aim for a CPUNB frequency of between 2400-2600 mhz on that CPU and the CPUNB volatge would need to be about 1.225-1.25 to support that. In your bios, CPUNB may be just called "NB" but don't get it confused with the chipset NB.

Your CPU core voltage is plenty high, maybe too high.

When you talk about temps are you referring to CPU (socket) temps or core temps? Core temps are the most valuable to know. If you will use HWMonitor it will display both as well as max, min and current readings of both plus board temps and voltages. I suggest you download and use that little piece of software. It's a standard around here.

Have you done any serious stress testing with Prime95 blend to check the stability of your overclock settngs as well as temps under full load? You want to keep core temps from exceeding about 55 C. because we known that with AMD CPUs instability starts to occur about then.

To change the timings you would need to go into that section of bios and take the main memory timing header off "Auto" and do the same for the sub menu items you wish to change.

 

[sirpatch]

Hey, i googled around and asus motherboards, at least mine, dont have the Command rate option on the bios have all timing options except that one.
Prime95 can work without errors during 6 minutes or so but then ..baam...and under full load core temp never goes over 43ºC
on my bios, the CPUNB voltage is called VDDNB, its at 1.25volts @ 2600mhz atm

 

[trents]

VDDNB would not be the correct item. Is there a VIDNB?

 

[sirpatch]

nope, there is not so i should back down VDDNB to auto?

 

[trents]

Yeah, you have very limited options in bios. I looked at your online manual. So, I would leave the CPUNB frequency at the stock 2000 mhz or slightly above that. What you definitely need to do is get your memory frequency down to within or slightly higher than its rated 1333 mhz. That would be "Memory Clock Mode". Take it off Auto and manually set it to 533/1066 to lower the starting frequency.

 

[trents]

nope, there is not so i should back down VDDNB to auto?

Yes.

 

[sirpatch]

What do you mean its rated 1333mhz? It says 1600 mhz
Im sorry i didnt get that part friend :s

 

[trents]

It will do 1600 if in XMP (Xtended Memory Profile) if you relax the timings. But you were telling me you cant' change the CR in bios. Otherwise, its 1333 ram.

 

[trents]

This is the case with essentially all memory sold as "1600".

 

[sirpatch]

So, how will i set it to 1333mhz in that case? Makes no difference to me for gaming effects.
If i set it too 667mhz DRAM frequency on the bios it will be a lot mroe than 1333mhz according to CPU-Z because of my overclock
I cant manually set FSBRAM ratio so i cant count on that
atm its 3:8 so i could try seeing if it stays at 3:8
and according to the equation 3:8=x/667, x=250.125 so if i set FSB to 250 then play with multippliers to reach the values i want, the ram will goto 1333mhz? but i have to count on the FSBRAM ratio staying at 3/8

 

[trents]

If your overclock settings will allow you to pass only 6 minutes of Prime95 blend then they need to be adjusted. I'm suggesting lowering your ram speed. If you can pass two hours of Prime95 blend then call it stable.

When you run Prime95 you should already have HWMonitor open on your desktop to monitor core temps. If they start to exceed 55 C. then you probably need to turn your CPU voltage down and lower your overclock (lower your FSB). That CPU may not do 3.8 with that cooler but it probably will do 3.6-3.7.

 

[trents]

Like I said in post #12, Go into Memory Clock Mode and lower the "divider" as we call it from the 1333 level to the 1066 level. It will be a ratio like 3:8 or 4:5 like you have already mentioned. Change it to something else so it winds up at a slower speed. If you were using a stock fsb of 200 mhz changing the ratio would show different standard DDR3 frequencies like 1066, 1333, or 1600. But since you raised the fsb above the stock 200 mhz what shows in CPU-z will be somewhere between those standard frequencies. Just experiment with the ratio until the end result is closer to 1333.

 

[sirpatch]

Alright trents thanks a LOT for your help
Once i experimented and just set the FSB so i could get 4ghz and my CPU with prime95 blend never went over 49ºC

Im going to try getting the ram close to 1333mhz
thanks sir
il keep you updated!