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Unlinked vs. Linked FSB:RAM

Heligrin

Limp Gawd
Joined
May 4, 2005
Messages
319
Hey guys,

I recently decided to re-overclock my system after having returned to stock speeds for an extended period of time.

My question is whether there is any performance degradation associated with running the FSB and DRAM at different frequencies, i.e i want to OC my e8400 to 3.7GHz, however, my DDR2 is rated for 800mhz (400), thus it would require me to OC my ram, which i dont want to do.

Thus, should i run my fsb @ 413 and my ram @ 400 or use a divider?
 
on an intel system the lowest you can get your memory is 1:1 with the FSB.. so if FSB is 413 your ram is 413.. what ram do you have? because if its ddr2 800mhz @ 4-4-4-12 then it should do ddr2 1066 @ 5-5-5-18 2.0-2.1v
 
on an intel system the lowest you can get your memory is 1:1 with the FSB.. so if FSB is 413 your ram is 413.. what ram do you have? because if its ddr2 800mhz @ 4-4-4-12 then it should do ddr2 1066 @ 5-5-5-18 2.0-2.1v
I have PC2-6400, thus its native speed is 800mhz (400x2).

What do you mean by the lowest you can your memory is 1:1? There are options within the bios, which allow you to independently set your RAM and FSB speed. This is why i was asking the question: is there an affect or problem with running your FSB higher than your memory speed?
 
I have PC2-6400, thus its native speed is 800mhz (400x2).

What do you mean by the lowest you can your memory is 1:1? There are options within the bios, which allow you to independently set your RAM and FSB speed. This is why i was asking the question: is there an affect or problem with running your FSB higher than your memory speed?


yeah you can set your ram to what ever you want in the bios.. you can set it to ddr2 400mhz but its still linked to your FSB.. the lowest you can set it is ddr2 400mhz thats 1:1 timing with the FSB.. so if you raise the FSB it raised the ram as well.. thus if you set the fsb to 413 your ram will be set to 413..

just because the native speed is ddr2 800 doesnt mean it cant be overclocked unless its some cheap generic ram with no heatsink..
 
yeah you can set your ram to what ever you want in the bios.. you can set it to ddr2 400mhz but its still linked to your FSB.. the lowest you can set it is ddr2 400mhz thats 1:1 timing with the FSB.. so if you raise the FSB it raised the ram as well.. thus if you set the fsb to 413 your ram will be set to 413..

just because the native speed is ddr2 800 doesnt mean it cant be overclocked unless its some cheap generic ram with no heatsink..

What you have said only applies if you have the ram LINKED. You do know you can unlink the ram speed from the FSB right? So he could set the ram at 400 but have his FSB at 500 if he wanted to.

As to the OP's question, I've ran RAM unlinked for years and never noticed a problem. Of course, you'd get more speed with a linked FSB and ram speed because your RAM would be at a higher speed. But keeping your DDR2 at 800mhz while overclocking the CPU isn't going to make a noticable difference. You will still benefit from the CPU overclock. I unlink my RAM and run it at 1000mhz while running the quad at 3.5ghz. I would suggest unlinking the ram, running it at 800mhz if it doesn't overclock well and then try to tighten the timings as low as you can. I've found tighter timings make a bigger difference then a small ram overclock.
 
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What you have said only applies if you have the ram LINKED. You do know you can unlink the ram speed from the FSB right? So he could set the ram at 400 but have his FSB at 500 if he wanted to.

As to the OP's question, I've ran RAM unlinked for years and never noticed a problem. Of course, you'd get more speed with a linked FSB and ram speed because your RAM would be at a higher speed. But keeping your DDR2 at 800mhz while overclocking the CPU isn't going to make a noticable difference. You will still benefit from the CPU overclock. I unlink my RAM and run it at 1000mhz while running the quad at 3.5ghz. I would suggest unlinking the ram, running it at 800mhz if it doesn't overclock well and then try to tighten the timings as low as you can. I've found tighter timings make a bigger difference then a small ram overclock.


huh interesting.. first time I've ever heard of LGA-775 having the ability to unlink ram clocks from the fsb..
 
huh interesting.. first time I've ever heard of LGA-775 having the ability to unlink ram clocks from the fsb..

I have never heard of it being called linked and unlinked, I have always heard it called a ram divider. Unless I am thinking of something else?
 
I have never heard of it being called linked and unlinked, I have always heard it called a ram divider. Unless I am thinking of something else?

Well on my nvidia 780i LGA775 board there is ram dividers as well. But you can also unlink your ram speed from your FSB and set them at independent speeds. Ram dividers can also help you overclock. Unlinking is just another tool to overclock with if you can't find the right divider.'

As to what a previous poster said, it may only be nForce boards that could do it on Intel LGA775. But I know for a fact that the nvidia boards do it as I am running unlinked right now. My ram is unlinked so I set it at 1000mhz while my CPU is a 3.5ghz on a multiplier of 8.
 
I no this thread is 3 months old. but I googled Linked ram or Unlink, And maybe one day some one else might have the same question and needs help. But Smut is Absolutly right!! I run a XFX 790i board. You can change the ratio or dividers, But you can also Unlink you'r ram from you'r cpu. Hence the Linked or Unlink. say u have a cpu that runs FSB @ 1333 and ram that runs 1600 if its linked, your ram wil run I do believe at 1333.. If you unlink it u can adjust ur ram seperate from the cpu. Another thing I have found. I adjusted my E8400 to run 1600 with is 3.60 and my chip has multiplier of 9. defualt the chip is 3.0 so what I did was. take 1333 raised it to 1600 devided it by 4 then multiplied it by 9. witch gave it 3.60 over clock so each FSB matched, 1600. But!! with them linked and if people has read my post befor I'm obsessed with windows index score.. lol Linked u get a score or point lower. Unlinked I got a Point higher. I hope in the future if any one else needs help and runs across this that it helps!!
 
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