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AMD 955 C2 Overclocking

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Heya guys I'm looking to upgrade from a 6950 to a 7950 so I've been advised to overclock my 955 CPU to elimnate bottlenecking.

Can anyone take me step by step on how to overclock this CPU maybe 3.6Ghz Something like that? :D
 
Soldato
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It is very simple, assuming you have adequate cooling, decent heatsink. The 955 has an unlocked multiplier so you can just go into the bios and change the CPU multiplier from stock 16x (3.2GHz) to 18x to provide 3.6GHz. Save the bios settings before exiting and reboot, this will not affect any other clock like memory, PCIe etc.

Check your CPU temps using HWmonitor and running prime95 simultaneously. Stay below 60C under load.

I would not expect a single 7950 to be significantly bottlenecked by a 3.2Ghz quad but you can check framerates in your games to find out at stock and overclocked.

Good luck, andy
 
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My wifes pc is a 955 BE chip and and at 3,2 she was getting bottlenecking playing multiplayer BF3 with a gigabyte windforce 7950.

I overclocked to 3,6ghz and the bottlenecking stopped so as long as you get at least 3,6 you will be good , these chips can do more but i didn't try to push it to far.

There is still plenty life in this cpu so best of luck and enjoy the new gfx card :)
 
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It is very simple, assuming you have adequate cooling, decent heatsink. The 955 has an unlocked multiplier so you can just go into the bios and change the CPU multiplier from stock 16x (3.2GHz) to 18x to provide 3.6GHz. Save the bios settings before exiting and reboot, this will not affect any other clock like memory, PCIe etc.

Check your CPU temps using HWmonitor and running prime95 simultaneously. Stay below 60C under load.

I would not expect a single 7950 to be significantly bottlenecked by a 3.2Ghz quad but you can check framerates in your games to find out at stock and overclocked.

Good luck, andy

Literally Just did what you said, Upped the Multiplier to 18x 3.6GHZ ran PRIME95 had HwMontior up and it crashed within 5 seconds - I obviously need some more volts? :D
 
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Its not a bad CPU for overclocking.

I'll list what i'm currently running to hopefully give you an idea.

I have a 965BE C3

I'm using K10stat to run the CPU at a variety of frequencies/voltages dependent on load because cool n' quiet is useless.

full load: 3.8GHz 1.425v
normal: 3.4GHz 1.26v
low load: 1.6GHz 0.85v
no load: 800MHz 0.8v

This leaves my system running very cool the majority of the time, 34C at the moment.

Do ditch the stock cooler though, after I saw a core go close to 100C when playing around with a 4GHz overclock I thought myself lucky to still have a CPU and bought another one.
 
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My 955 C3 is strange. It likes 3.6Ghz @ 1.35v, 27c idle temps!

but won't settle at 3.7-9Ghz without 1.475v or 1.5v :(

Thinking of buying a 7950 so 3.6Ghz should be enough until I upgrade to intel in the distant future.
 
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When what's the recommended voltage for 3.6GHZ?

Depends on the CPU to some extent. My 1055T runs 3.5GHz at 1.375V which is less than the stock vcore of 1.45V. I have to OC using the cpu busclock as I have locked multipliers so I use 250MHz x 14. This method means you have to alter the memory multiplier as well as NB multiplier

I do not know what you have set in the bios but you are safe up to vcore 1.475V and probably more but am not going to say 1.5V and you burn out the processor.

What cooling have you got and what heatsink. A standard heatsink will not allow 3.6 and that could be your problem.

But first try 16.5x (3.3) with Prime and if that passes try 17x see what your limits are
 
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Sounds awful I don't really want to spend soooo much time doing it can I just put it at 1.45 and be done with it? :D
 
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Sounds awful I don't really want to spend soooo much time doing it can I just put it at 1.45 and be done with it? :D

Can do that, but you will never really know if it's stable, so always be prepared for a system failure and possible loss of data.

That said, when it does crash you'll know to up the vcore :)
 
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I know all chips are different but i read somewhere (cant remember where) that they all o/c to 3.7/8 on stock volts,i recently purchasd a c3 and sure enough got 3,8 stable just by upping the multi,howver above that the voltage went up steeply and i had to use 1.5 volts on the vcore to get stable at 4ghz,i dropped down to 3.9 and it runs happily at 1.45v and i use this all the time,and i now have no bootlenecking on my o/c gtx470
 
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