which is better for overclock, keep memory at 1:1, or use another divider?

HotL3@D

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I can get my cpu up to 3.2, possibly further with some better cooling, but my ram seems to be the limitation. she doesnt like to overclock 1:1 much past 216, and then one of my pci devices decides to bitch (probably the HD) because of the overclocked pci setting. I got the cpu up to 3.2 with a 5:4 divider on the ram with 2.5-6-2-2 timings and she was stable at that point. is it worth it though? it seems underclocking the ram hurts performance enough to yield only nominal gains from the overclock. I actually got more performance from 3dmark03 from overclocking the vid card at normal cpu speeds than i did with keeping the vid card at stock speeds and the cpu at 3.2....

Maybe i should overclock the vid card to its highest stable potential and then begin try overclock to 3.2 with the ram divider set ti 5:4 and see what i get then?

There was a question somewhere in all this... i lost track of it though :D any suggestions, what would you do?

I also put all the mem timings down to their lowest setting and overclocked 1:1 divider to 3.2 GHZ (233FSB), but it seems its another trade off, higher cpu, but tradeoff of the hurt performance for the bad ram timings, yielding only a slight gain.
 

PureBooYah

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If you were running an AMD XP system i would say stick at 1:1...but with intel if you can clock higher by dropping the ratio to 5:4 then that will give you the best performance. It will especially give you more performance if you can drop the memory timings down too.
 

HotL3@D

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PureBooYah said:
If you were running an AMD XP system i would say stick at 1:1...but with intel if you can clock higher by dropping the ratio to 5:4 then that will give you the best performance. It will especially give you more performance if you can drop the memory timings down too.


seems though that the trade offs for dropping the ratio seem to yield negligable gains for that amount of overclock. See what i mean? I mean, its still a nice boost, but the ram is underclocked to 198mhz at 5:4...
 

PureBooYah

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well what are you memory timings at your highest 1:1 overclock?

dropping the ratio from 1:1 to 5:4 is only around a 2% drop in performance, so tightening the timings can make up for that 2% performance loss. Take a look at this post over at xtremesystems... http://www.xtremesystems.org/forums/showthread.php?postid=186867#post186867 ....also if you can overclock the cpu higher with 5:4 (it doesn't take much) along with tightening the timings you can get more performance than running at 1:1 with loose timings.
 

HotL3@D

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PureBooYah said:
well what are you memory timings at your highest 1:1 overclock?

dropping the ratio from 1:1 to 5:4 is only around a 2% drop in performance, so tightening the timings can make up for that 2% performance loss. Take a look at this post over at xtremesystems... http://www.xtremesystems.org/forums/showthread.php?postid=186867#post186867 ....also if you can overclock the cpu higher with 5:4 (it doesn't take much) along with tightening the timings you can get more performance than running at 1:1 with loose timings.

Ahh, i see, that makes sense, actually. considering at my stock speed i'm running ram at 200 mhz, and at 5:4 at 233 FSB, the ram is at 186 (I believe? or 198), with pretty tight timings. 2.5-6-2-2, though i could probablyr run 2-5-2-2.
 

kronchev

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HotL3@D said:
seems though that the trade offs for dropping the ratio seem to yield negligable gains for that amount of overclock. See what i mean? I mean, its still a nice boost, but the ram is underclocked to 198mhz at 5:4...


and he has it wrong, intels get HUGE boots with sync mem, while XPs do get a big boost but not nearly as huge
 

chrisf6969

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Ummm, your PCI bus shouldnt be affected by the overclock. Make sure you have AGP ratio set to: FIXED (not 8:2:1, etc..) then set it to 33/66 manually.
AGP ratio: FIXED
AGP/PCI: 33/66

I'm thinking you probably dont have your PCI/AGP bus locked!!

And Kronchev has it wrong, PureBooyah has it right.
AMD benefits much more from sync memory.
Where Intel its a toss up depending on speeds and timings.
at 250FSB 1:1 with loose timings 3-4-4-8
vs 250FSB 5:4 with tight timings 2-3-2-6 or better
most benchmarks (not all) are better with the ratio. Its been proven many times.
ex: 3dMark2001 will score a lot better with ratio & tight timings +500-1000pts
3dMark2003 will score a little better with 1:1 and loose timings.

And thats apples to apples comparison same CPU speed, same FSB speed, just different ram ratio & timings.

But if the ratio lets you overclock more its usually an obvious win for the ratio vs 1:1. B/c CPU speed raises your benchies faster than ANYTHING else. (OC'ing Mhz wise, not counting a whole new videocard)
 

HotL3@D

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chrisf6969 said:
Ummm, your PCI bus shouldnt be affected by the overclock. Make sure you have AGP ratio set to: FIXED (not 8:2:1, etc..) then set it to 33/66 manually.
AGP ratio: FIXED
AGP/PCI: 33/66

I'm thinking you probably dont have your PCI/AGP bus locked!!

And Kronchev has it wrong, PureBooyah has it right.
AMD benefits much more from sync memory.
Where Intel its a toss up depending on speeds and timings.
at 250FSB 1:1 with loose timings 3-4-4-8
vs 250FSB 5:4 with tight timings 2-3-2-6 or better
most benchmarks (not all) are better with the ratio. Its been proven many times.
ex: 3dMark2001 will score a lot better with ratio & tight timings +500-1000pts
3dMark2003 will score a little better with 1:1 and loose timings.

And thats apples to apples comparison same CPU speed, same FSB speed, just different ram ratio & timings.

But if the ratio lets you overclock more its usually an obvious win for the ratio vs 1:1. B/c CPU speed raises your benchies faster than ANYTHING else. (OC'ing Mhz wise, not counting a whole new videocard)

Okay, i'm here running windows with a 233FSB and a 5:4 divider So i'm at 3.2GHZ CPU and 233FSB/186 Ram. My CAS Is 2-5-2-2. mem is at 2.8V and my CPU is at stock voltage running 51C idle. Case is 34C. I think the CPU has more in her.

Also, i noticed that the AGP/PCI bus were locked in the bios but they still seemed to change when i changed FSB settings. By "locked" do you mean that the MB is setting the Ratios automatically (which is what it is set to) I.E. 8-2-1, 7-3-1, whatever...

Edit:// Just ran 3dmark03, no problems got a 6730. I wanna start overclockin the vid card now :)

Gonna run prime95 for a while see if shes stable..
 

chrisf6969

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HotL3@D said:
Also, i noticed that the AGP/PCI bus were locked in the bios but they still seemed to change when i changed FSB settings. By "locked" do you mean that the MB is setting the Ratios automatically (which is what it is set to) I.E. 8-2-1, 7-3-1, whatever...

Edit:// Just ran 3dmark03, no problems got a 6730. I wanna start overclockin the vid card now

Gonna run prime95 for a while see if shes stable..

No, change the setting for AGP ratio in the BIOS...

you will have the options of auto, 8-2-1, 7-3-1, etc, or FIXED.

you want "FIXED" for the best stability and highest possible overclock.

875/865 mobos are over a year old, this is Basic Overclocking 101. Pay attention! :)

P.S. what was your 3dMark score before Overclocking?
 

TheRapture

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kronchev said:
and he has it wrong, intels get HUGE boots with sync mem, while XPs do get a big boost but not nearly as huge


My Mobile chip gets much better benches at 2380mhz (170x14, ram and cpu synch) vs. the slighly higher clock of 2400mhz (200x12, ram at 166, cpu at 200). ESPECIALLY in Far Cry, much smoother, less stutter, not to mention my 3DM03 scores go up about 500 points...

If I had better ram I could get even more speed since I could run both cpu and ram at 200fsb and get alot faster memory benches. I WILL be getting some good PC3200/3500 soon though...
 

HotL3@D

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chrisf6969 said:
No, change the setting for AGP ratio in the BIOS...

you will have the options of auto, 8-2-1, 7-3-1, etc, or FIXED.

you want "FIXED" for the best stability and highest possible overclock.

875/865 mobos are over a year old, this is Basic Overclocking 101. Pay attention! :)

P.S. what was your 3dMark score before Overclocking?


I am paying attention!! :) i just didnt see fixed in that ratio change menu, i'll give it a try! Thanks! BTW, how does it keep the agp/pci bus fixed? What magic is this? BTW, i started off overclocking a pentium 3 800mhz what seems like many years ago, i have a basic understanding of what i'm doing, but i havent kept up witht he technology of overclocking lately...

Btw, 3dmark03 before was 6540.

EDit:// HEY! well lookie there! There is a 'fixed' setting!! now at 3.4 GHZ..
 

HotL3@D

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I'm thinking of picking up a zalman heatsink for quietness and good cooling what you guys think?
 
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