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Help for a NOOB please

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Ropedog

New Member
Joined
Feb 21, 2008
Location
Lancaster, PA
Glad I found this forum, it has been a big help... Tons of good info.
Anywho...
I receintly bought 2 sticks of 1gb corsair ram (6400) and installed on my machine. The FSB speed should be able to go to 400mhz (400*4 = 1600 for quad pumped) right?

Problem is that I cannot get it stable over about 1120mhz (1120/4=280mhz)

I hope I explained this well enough. Anybody have any suggestions?
I'm going to write my system info in my sig soon, but for now:

E6600
XFX 680i LT
Antec 500W PSU (earthwatts)
2gb corsair 6400 ram
EVGA 8600GT
 
effective memory speed is not the FSB*4, it's the FSB*2. IE DDR2-800 memory runs at 400x2=800mhz.

Hope that answers your question.
 
I have had the memory set to 1:1, 3:2, and 5:4, but at no time would it work above 1120mhz (speed at the memory).

All this multiplying and dividing crap is confusing.

As I understood, the actual FSB speed is (effective FSB) / 4 due to the quad-pump
Example: 1200mhz / 4 = 300mhz (actual)

6400 mem is 6400 / 8 = DDR800, which is twice the actual frequency...
Thus: 800mhz / 2 = 400mhz (actual)

It is these "actual" FSB speeds that I was using.

This is not correct thinking?
:bang head
 
Keep it simple.

CPU = Quad Pumped.

400FSB * 4 = 1600 'rated' FSB

Memory (double data = *2, memory at 1:1, 400MHz = DDR800)
 
First, :welcome: to the forums!!! :beer:

The Intel CPU data rate is quad pumped, i.e. 4*FSB, not the memory.

Memory is DDR (Double Data Rate), i.e. 2*FSB. 6400 memory is rated at a data rate of 800 = 2*400 where 400 is the correspond FSB speed to run the memory at its rating. This is just the manufacturer's rating of the memory and you can run it faster and in the case of your 680i you can run it slower.

Second, have you tested to make sure that you have a memory problem? It sounds like you've not unlinked your memory.

What are your CPU voltage and northbridge voltage?
 
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First, :welcome: to the forums!!! :beer:

The Intel CPU data rate is quad pumped, i.e. 4*FSB, not the memory.

Memory is DDR (Double Data Rate), i.e. 2*FSB. 6400 memory is rated at a data rate of 800 = 2*400 where 400 is the correspond FSB speed to run the memory at its rating. This is just the manufacturer's rating of the memory and you can run it faster and in the case of your 680i you can run it slower.

Second, have you tested to make sure that you have a memory problem? It sounds like you've not unlinked your memory.

What are your CPU voltage and northbridge voltage?

OK, let me make sure I'm reading this right...
If I have my FSB set at 1400mhz, and the memory at 1:1...
1400 / 4 = 350mhz, which is the actual FSB, which would give me 3.15ghz for the processor.
The memory, at 1:1, would be running at 350mhz (DDR700), right?

Right now I have the memory at 3:2, FSB at 1400 (or 350mhz)... runs good, but the memory is only running at 233mhz (350 * 2/3)... or, is it running at 933mhz and it is already overclocked. (Hope I'm not rambling!)

My voltages are usually around
1.4 - 1.425 for the processor
1.3 for the motherboard FSB
anywhere from 2.0 - 2.3 for the memory, but I have tested all the way to 2.5v.
 
1400FSB at 3:2 would result in 933Mhz RAM, correct.

It can get kind of confusing. Glad my motherboard just allows me to put in any speed unlinked to each other ;)

-Chris
 
Sorry for beating a dead horse here, but I need to understand this or it's gonna drive me nuts.

If I have my cpu fsb set at 1400, that number is quad pumped. The actual cpu fsb is 350mhz.
If my memory ratio is 1:1, the frequency for the memory should be 350mhz, right? My BIOS says its 1400 though.
What is my memory opperating at:
A) 350mhz (DDR700)
B) 1400mhz (DDR2400)
C) 700mhz (DDR1400)

I'm starting to lean toward (C).

Let me see if I have this right, again:
350mhz fsb at the cpu
due to the quad pumping, the cpu is effectively 1400mhz
the memory will then operate at 1400mhz at a 1:1 ratio, thus, 700mhz (DDR1400)
For DDR800, this is a HUGE overclock.

How's this?
 
Sorry for beating a dead horse here, but I need to understand this or it's gonna drive me nuts.

If I have my cpu fsb set at 1400, that number is quad pumped. The actual cpu fsb is 350mhz.
If my memory ratio is 1:1, the frequency for the memory should be 350mhz, right? My BIOS says its 1400 though.
What is my memory opperating at:
A) 350mhz (DDR700)
B) 1400mhz (DDR2400)
C) 700mhz (DDR1400)

I'm starting to lean toward (C).

Let me see if I have this right, again:
350mhz fsb at the cpu
due to the quad pumping, the cpu is effectively 1400mhz
the memory will then operate at 1400mhz at a 1:1 ratio, thus, 700mhz (DDR1400)
For DDR800, this is a HUGE overclock.

How's this?

In your example the FSB (Front Side Bus) is running at 350Mhz, end of story. The speed of this bus is controlled by a clock. A tick is equal to (1.0/350Mhz) for this example, or 2.8571 nanoseconds. Just in case you don't know it, one hz (hertz) is = cycle/second.

Everything else relates to the speed of the FSB.
For example memory speed = 2*FSB or 700 when the memory ratio is set 1:1 (read as 1 to 1).

Consider now the 680i bios. The 680I bios lets you to input "FSB (QDR), Mhz" which happens to be 4*FSB or the CPU FSB. My guess is that this is where the confusion arises. Most other motherboards will just ask for the FSB, not the CPU FSB. In principle, it really doesn't matter whether you ask for the FSB or the CPU FSB because you can get one from the other.

Next, with your bios you have an option to run your memory either linked or unlinked. If you don't have an electronic version of your motherboard manual, download one. Then search for linked and unlinked.

Select the "Unlinked" for the "FSB - Memory Clock Mode" option. This allows you to run the CPU's speed and memory speed completely separate from one another. You can now tell it the memory speed you want, type in the Mhz you want. Selecting the unlink option skips the choice of ratios.
 
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Thanks for the help all.
I found out that if I set the link ratio to "sync", the memory sets itself to the actual FSB speed.
But, when I was using 1:1, the memory was matching the quad pumped frequency. This is where I was getting confused.

So, I ended up getting close to 3.4 or 3.5Ghz on my E6600 (stable) with a sync'd memory ratio. Not too bad, I'm happy.
Next, I see that I need to upgrade to Vista64 so I can use the rest of my memory.
 
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