I need professional help!

[knowsitall]

1:1?? does that mean that your ram and cpu are both being ran at the same fsb?? for example if you had 200fsb ram (400mhz ram), and a 200fsb (200*4 800fsb) pentium d. that would be a 1:1 right??

if i am right then what is 5:4? what is 4:5 ? what is the differencE? how would one know when it is better to have a higher fsb on ram then cpu? or how to know when to have higher fsb on cpu then ram??

 

[Jizumonkey]

I always found the terminology slightly confusing also but 1:1 does not mean running the FSB at 800MHz for 800DDR2 RAM, it means running your FSB at 400MHz, multiplier at 2x. The secret I guess is remembering what DDR stands for, double data rate i.e two bits per clock cycle, so effectively at the 'same' speed it is doing twice the work.

My setup below runs 400FSB, 2x multiplier for 800DDR2 and this is called 1:1 maximum extraction. Go bench your system and see for yourself, your memory bandwidth will improve even though previously you may have run it at stock speeds also (my 800 is not overclocked) but at a different FSB and ratio.

The down sidd to this is when overclocking your CPU. 400MHz increments are rather large steps - I have to go from 2.4GHz to 2.8 to 3.2 etc.

 

[knowsitall]

My setup below runs 400FSB, 2x multiplier for 800DDR2 and this is called 1:1 maximum extraction.

So what would a 533mhz ram 1:1 be? 266.5 *2 rite?
so what is 2:1 or 5:4 or other settings like that i have seen??


Also i know it is possible to run 800mhz ram at say 533mhz (clock down the ram). So would it be better to clock down 800mhz ram to 400mhz ram (200*2) to run with a processor with a 800fsb (200*4). Wouldnt this mean that both the processor and ram are running at a base of 200mhz (200 * 4 =800fsb processor, 200 *2 = 400mhz ram) giving a better and faster pc for gaming and benchmark results>? also running the ram at 200*2 to match the processor, doesnt this give alot more headroom for overclocking on 800mhz ram?? If this is not true. Then what ram settings compared to cpu setting do give best results? what ram settings vs cpu bus is best for overclocking?? how would one know what ram speed is best matched with a cpu to eliminate any cpu to ram bottlenecks or vise versa??

i have alot of questions.. anyone have answers?

 

[Jizumonkey]

OK well the Pentium D is an 800 MHz device quad pumped from a 200MHz bus as you know. Well 200 doesnt go into 533 so already you have an odd ratio of around 2.5:1 on your mem multiplier, and this is where you see the strange figures you asked about - when the memory speed doesnt match the FSB set for the processor.

It all depends on your motherboard past this point I'm afraid, if you have a good one you will be able to set this manually, if you have a cheap one you will not, and also most likely not be able to adjust the CPU multiplier either.

Assuming you can set your FSB manually, give it a go at 266 but dont forget to lower your CPU multiplier accordingly aswell or it'll oc too far and crash.

i.e FSB=266, mem multiplier = 2x, CPU multiplier = x11 (though the CPU doesnt match properly now you are under clocking at 11x and slightly overclocking at 12x...see?)

 

[knowsitall]

OK well the Pentium D is an 800 MHz device quad pumped from a 200MHz bus as you know. Well 200 doesnt go into 533 so already you have an odd ratio of around 2.5:1 on your mem multiplier, and this is where you see the strange figures you asked about

couldnt i just drop my ram to 200*2 instead of increasing my cpu to 266/1066 which would cause more heat that my stock cooling could not handle?


i belive i have seen people running their cpu's at 350fsb/1400mhz and their ram at 400fsb/800mhz?? why would someone do this? this is where i m lost. does it make more sense to run both the cpu and the ram at the same BASE fsb?? or does it nott matter at all?

 

[Estrang]

OK well the Pentium D is an 800 MHz device quad pumped from a 200MHz bus as you know. Well 200 doesnt go into 533 so already you have an odd ratio of around 2.5:1 on your mem multiplier, and this is where you see the strange figures you asked about

couldnt i just drop my ram to 200*2 instead of increasing my cpu to 266/1066 which would cause more heat that my stock cooling could not handle?


i belive i have seen people running their cpu's at 350fsb/1400mhz and their ram at 400fsb/800mhz?? why would someone do this? this is where i m lost. does it make more sense to run both the cpu and the ram at the same BASE fsb?? or does it nott matter at all?

Correct me if I'm wrong, but I believe the memory and cpu are running off the same FSB. And if this is true, then the only way to get your ram to run at 200*2x would be to downclock your FSB to your cpu as well. The only way to change ram frequency as far as I know besides changing the latency timings is to lower/raise FSB on whole computer or change the ratio. In your case you have DDR2 800 running on a 200 FSB. So for it to run as 800mhz without raising your FSB speed you need to change the ratio to 2:1. The formula would be 200mhz*2x where x= the ratio so:
200mhz*2*(2/1)=800mhz.

EDIT: I see you want to downclock the speed to 533mhz, I realize now that there is something missing in my formula as it doesn't account for how this can be accomplised.

 

[-silencer-]

That's just a ratio of fsb speed to memory speed. People refer to 1:1 because it's beneficial to run synchronously, but some benchmarks do well with as fast as memory as possible.

We'll take th 1066MHz fsb E6600 for example. Since the Conroes are QDR (Quad data rate), the motherboard fsb is 266MHz. Since memory is DDR (double data rate), then RAM is at 533MHz at a 1:1 ratio. If we set the memory speed divider at 4:5 (fsb is 4, ram is 5) and the fsb is at 266MHz, the RAM will be at 667MHz.

Simple algebra. 266/4 = x/5. Solve for x.. x=333 (DDR is 667)

Now if we overclock the fsb to 400MHz, the E6600 is now running at 3.6GHz, and the memory at 1:1 is at 800MHz. If we had RAM that can't go to 800MHz, we'd have to use a lower memory divider.. like 5:4.
400/5 = x/4.. x=320 (DDR 640), so perhaps our DDR2-533 could overclock to 640MHz.. if it can't, we'll have to try a lower memory divider (ratio).

The memory divider gives us flexibility like the cpu multiplier. It allows us to fine tune the speed of just that one component without being dependant on the rest of the system.

 

[knowsitall]

ahh ha your making sense to me -silencer-. great you seem to know you sh*t pretty good. with all this mumbo jumbo talk i didnt think anyone knew what the hell i was asking. but yah thanks alot you helped clear shit up for me u know ur shit.

 

[Dahak]

Yes that is correct.When you run 1-2,you have the cpu at 200 and the memory at 166.Goodluck.

Dahak

AMD X2-4400+@2.6 S-939
EVGA NF4 SLI MB
2X EVGA 7800GT IN SLI
2X1GIG DDR IN DC MODE
WD300GIG HD
EXTREME 19IN.MONITOR 1280X1024
THERMALTAKE TOUGHPOWER 850WATT PSU
COOLERMASTER MINI R120

 

[knowsitall]

Yes that is correct.When you run 1-2,you have the cpu at 200 and the memory at 166.Goodluck.

hm how is a 1:2 200 166?

 

[Dahak]

When you are running at 1-1 your fsb and ram are running at the same speed.But when you run at 1-2,your fsb is 200 and ram at 166.

Dahak

AMD X2-4400+@2.6 S-939
EVGA NF4 SLI MB
2X EVGA 7800GT IN SLI
2X1GIG DDR IN DC MODE
WD300GIG HD
EXTREME 19IN.MONITOR 1280X1024
THERMALTAKE TOUGHPOWER 850WATT PSU
COOLERMASTER MINI R120

 

[-silencer-]

Yes that is correct.When you run 1-2,you have the cpu at 200 and the memory at 166.Goodluck.

hm how is a 1:2 200 166?

Yeah I'm curious too.. this something different with AMD HTT system? I never messed with memory dividers until 5 months ago building and overclocking various C2D/Q machines.. 200 fsb, 166 ram is a 6:5 ratio.. 333MHz RAM in DDR. Perhaps you're using DDR PC-2800 memory or such?

 

[tik]

many thanks to you -silencer-

 

[architecture1]

ahh ha your making sense to me -silencer-. great you seem to know you sh*t pretty good. with all this mumbo jumbo talk i didnt think anyone knew what the hell i was asking. but yah thanks alot you helped clear **** up for me u know ur ****.

I agree! Silencer is like a buddah intertwined in the cyberspace forest... well I'm rambling...

Seriously, that all made sense of a subject I was just wondering about myself.

My question is, is it a problem if I am verry close or right @ 800MHZ w/800MHZ-RAM?