Can't figure out how to overclock memory on my MSI K8N Neo.

HockeyZ39

Member
Dec 22, 2004
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***Sorry for the newb question!***

I have read alot of over clocking guides and from what I understand to raise your FSB your need to raise your RAM as well (I have a gig of Kingston hyper-x pc3200 ram.) Now when I go into the bios I do not see any option for raising RAM. I have bumped up the FSB up to 230, 225, 220 and all were unstable on my 3200+ Newcastle (they failed prime95 about 20 seconds in.) Is there a menu I am missing or something or am I going about it all wrong in the first place? TIA for any help
 

HockeyZ39

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Dec 22, 2004
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Also my MSI mobo has "Dynamic Overclocking" which has different settings that I can select where it automatically overclocks the CPU when it is running at full load. It has settings from 1%-11% but when I enable this, the computer will not even boot and I have to reset the BIOS using the pins.
 

GuitarDaddy

Lifer
Nov 9, 2004
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Ram doesn't have a seperate bus speed, it runs at a ratio of the CPU bus. The default setting is 1:1 which means the ram runs the same speed as the CPU bus.

Stock CPU bus for AMD's is 200mhz

3200+ has a max multi of 10, 10x200=2000mhz or 2.0ghz
memory 200x2=DDR400

If you overclock to 2.5ghz 10x250 and use the 1:1 setting your ram is running 250x2=DDR500

You need to locate the memory ratio(divider) settings on your mobo. Different mobos list them differently

200,DDR400,1:1 runs ram same as CPU
166,DDR333,6:5 runs ram at aprox. 5/6 of CPU speed
133,DDR266,3:2 runs ram at aprox. 2/3 of CPU speed
100,DDR200,2:1 runs ram at aprox. 1/2 of CPU speed
 

Uhtrinity

Platinum Member
Dec 21, 2003
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It also varies depending on the cpu, the X2's actually have higher ratios, ie upto 4:5 (500 DDR on a 200Mhz fsb).
 

HockeyZ39

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Dec 22, 2004
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Oh ok, so I need to drop the memory ratio divider. If I had higher ram (ddr500) I could just throw up the FSB and have no problems?
 

GuitarDaddy

Lifer
Nov 9, 2004
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Yes DDR500 and above is rated to run at an overclocked speed. Depending on your ram, many DDR400 rams will overclock to DDR500 or higher. My OCZ plat. r2 PC3200(DDR400) ram will run 287mhz(DDR574).

When overclocking ram you have to loosen(increase) the ram timings. For example if your ram is rated 2-2-2-5 at 200mhz(DDR400) you would have to go to 2.5-3-3-8 at 250mhz(DDR500) and you might have to increase the DDR volts.
 

HockeyZ39

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Dec 22, 2004
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I am planning to get some DDR500 that runs at 2-2-2 for my next comp, will using a divider on the ram slow the computer/ram down at all?
 

HockeyZ39

Member
Dec 22, 2004
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Ok so I couldn?t find any option to divide the ram, I just updated my bios to 1.9 and still nothing. Do I not understand correctly? I was thinking there would be option to do FSB X (what ever divider) for the ram? Also ClockGen has the "clock" part grayed out for me, I read on the site to set high performance mode to "auto" but the only options I have are "optimized" and "manual" both still cause the button to be grey. TIA for any help!
 

HockeyZ39

Member
Dec 22, 2004
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I recently noticed an option that says somthing to the effect of limiting the ram speed. Is this what I would use to divide the ram? Set the ram "limiter" to 166 so when I oc the FSB the ram is going up from 166? TIA