Cant raise memory clock of msi 6850 oc pe when overclocking

Zephyron

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Nov 6, 2011
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hey.
so yesterday i decided to try and overclock my msi 6850 oc pe using afterburner.
i installed afterburned and stared raising the core clock from the defaul 860 and up without adjusting the voltage. i got to 965 (i used kombustor to check for stability and after 90 minutes of stress test the 965 value proved to be quite stable)
next i tried to raise the memory clock. i raised it from the default 1100 to 1110 and run kombustor. the card crashed after 10 minutes. i lowered it to 1105 and the program crashed after 15 minutes. why?
on other various overcloclocking reviews of the msi 6850 oc pe people had various results in overclockign the card (obviously) but everyone managed to raise the memory clock to AT LEAST 1125 (im talking bout the minimum while some were able to get 1200 but WITH voltage tuning). the 965 mhz value i got out of the core clock seems to be the average if not a TAD above average when compared to other ppl, while not having to adjust the voltage.
so how come i can raise the core clock easy enogh without adjusting voltage, and not the memory?

*also when i say that the card crashed i mean that the kombustor screen just went black and froze up so i had to END TASK the thing. i didnt get the "display driver crashed and recovered" alert,. when kombustor's screen goes black that DOES mean that the card crashed right?
 
Solution
I always recommend OCing the memory first. You can't adjust memory voltage so it's good to find the highest mem speed first. Even though the voltage can't be adjusted, there does seem to be some link between the core and memory, so basically in theory a lower core clock will probably get you a higher memory clock.

Other than that, though, just means you got unlucky with the card.
 

Zephyron

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Nov 6, 2011
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some of the overclocking guides said to overclock the core mhz first and leave the memory clock for later, after u have established a stable clock speed. also the overclocking guides about the msi 6850 oc pe i read said that the ppl who did the overclocking adjusted the core first and then the memory.
and i think you CAN adjust the memory voltage with afterburner. or am i wrong? should i mess with that?
 

Zephyron

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Nov 6, 2011
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hmm they might do some maintenance at anandtech coz cant see the link. i can see in these review however
http://www.hardocp.com/article/2011/02/08/msi_r6850_cyclone_power_edition_video_card_review/8
http://www.ocia.net/reviews/msir6850/page3.shtml
http://www.overclockersclub.com/reviews/msi_r6850_cyclone/4.htm
that OC both the core and memory should be no problem even without uping the voltage. i suppose ill have to try to lover the core clock and see if that enables me to up the memory clock. feel kinda bad to have to lower the clock since it so damn stable at 965. any other ideas?
 

Zephyron

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Nov 6, 2011
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ok anandtech is back online. just saw the review and its quite interesting. i saw that at least in their tests a 940/1150 is only, like, ONE frame faster than 960/1150. but this review is about the msi 6850 oc. i have the msi oc PE which has a higher stock clock of 860 mhz.
but anyway i will try lowering the core clock and see if that enables me to up the memory. if you have some advice it will be appreciated.
also would like to hear some more OC results from ppl who have this card.
 

Airberg

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Apr 30, 2012
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Using afterburner u should b able to up the voltages of all 3. Not just core clock.

http://www.bit-tech.net/hardware/graphics/2011/04/01/msi-radeon-hd-6850-cyclone-power-review/8

Using their oc settings posted, the vid card is stable using full graphics on any game I've tried. And the gpu doesn't go above 62 while benchmarking.

EDIT: http://www.hardocp.com/article/2011/02/08/msi_r6850_cyclone_power_edition_video_card_review/8

This is the OC settings above what out of the box is.
http://www.hardocp.com/image.html?image=MTI5NTE0NzM0OWVaV0ZTeGh6S0tfOF8yX2wuanBn

This is the OC Voltages for the new settings.
http://www.hardocp.com/image.html?image=MTI5NTE0NzM0OWVaV0ZTeGh6S0tfOF8zX2wuanBn
 
Solution

TheProudNoob

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Jun 7, 2012
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I'm topped out at 970 / 1200, although I think I can push the memory to 1250 or higher. Stock voltage. With higher voltage, I can reach 1 GHz.