955 BE, I want 4.0 stable. How to...

spks19

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Feb 3, 2010
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Alright, theory time.

I have my 955 stable at 3.8 with stock frequency and just running the multiplier at 19.0.
so 200mhz freq X 19 = 3,800.
For 4,000 all I would have to do is raise the multipler to 20... right? Well it crashes.
Temps don't even get a chance to raise, you tell it to go up and it just stalls and goes black.

I am wondering what other methods might get this thing to 4.0 stable.

Components and mobo boot settings.
ASROCK M3A770DE
2 gb PC 12800(1 dimm) OCZ DDR3Black Edition RAM @ 800 mhz (1600 mhz capable) 6-6-6-15 (8-8-8-24 @ 1600)
Phenom II 955 3.2 stock, 3.8 current (42 idle) 200 mhz, 19 multipler, 1.440 volts (cpu-z rated)
Cooler Master Hyper 212 Plus


I can get it to sit at 3.986 when I turn the HT down to 6, and the frequency to 190, but as soon as I try to run a benchmark it crashes.

Moved multiplier up to 19.5 while typing this message, still stable...
What else can I do?

-spks19
 

isamuelson

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You might not be able to make it to 4 ghz. That's the other issue. It all depends on your memory, motherboard and cooling. Where you're at is pretty good, but would getting to 4 ghz REALLY gain you that much more performance from 3.8?
 

zerkerdude

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I'm happy with 3.9 not much performance boost to 4.0 I had to bump up the voltage a lot to get 4.0 stable. I had it in my brain that I wanted at least 4.0 but it took a lot more voltage/heat to bump it up that little bit and my temps were getting up to about 64c after running Prime95. Granted Prime95 overloads all your cores and would probably never get that high under normal use. BTW I'm using the same cooler that you are. But my ambient temps get up to 80F so I gave it some leg room. I bet you can get it to 4.0 but at what cost? Overvolting/Overheating?
 

spks19

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Well the future will probably hold some lapping of the processor and the heatsink. I will most likely upgrade the fan on this heatsink, as the stock one that came with it makes an annoying rattling sound when you turn it up past 8. I will do some voltage raises once the new hexacores come out so I can buy one of them to replace this one if I fry it. For now, I am just running it at stock settings as I too have insane ambient temperatures. If I leave this thing on overclocked, the room gets to 80 easily making it that much harder to keep it cool. I've been doing the ocing without raising the voltage merely because as soon as you start ocing you void your warranty. You can overclock all you want and as long as you don't overvolt it, the chip won't fry. You may have to remove the CMOS battery to reset to factory defaults, but to my understand you cannot fry it by heat alone, they shut themselves off.

-spks19
 

midlifecr1515

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Apr 23, 2010
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I got my AMD 940 to run very well at 3.7. At 3.8, I have to put the voltage to 1.55v (maximum) and after an hour or two, it will glitch and BSOD on me. I have the $60 Zalman cpu cooler to keep it at a comfortable 36-40 degrees C at full tilt.
In my Bios I enabled memory flexibility and manually typed in the tRAS, etc. Also turned off spread spectrum for the cpu because I read that it can cause instability at higher clock speeds. You might try that. Another thing I've learned is that increasing system clock speeds effects other components connected to that system and some don't run well or at all at higher speeds, i.e. your HDD, etc.
I was wondering if anyone could tell me...If the bios has a default warning not to use higher than 1.55 voltage for the cpu, does that mean even with an after market cooler like my Zalman? I don't reach higher than 40C while playing BC2 at max dx10 eye candy for several hours. But I really am curious to see if I go to 1.56v I can run at 3.8 stable or even 3.9. I also leave my NB at x10 @ 1.17v... Would it help or be worse to increase that?
 

spks19

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I've read conflicting results. Some seem to think the the Northbridge is the motherboard chip, while others claim it to be part of the cpu that powers the cache. Until I know better, i'd not fiddle too much with the voltage on it. I'll read up on the spread spectrum.

I like to lower some settings, especially RAM related, so that once you overclock the cpu, the RAM and the HT will be at their normal operating speeds. Since the mulitpler is often shared you need to adjust accordingly. However, I think what happens here, is the CPU just heats up and you gain 0 performance since you are effectively creating a bottleneck.

-spks19