800 or 1066 mhz ram ? and ratios :s

mazza7282

mazza7282

mazza7282

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I plan to get myself a E6600 Core 2 Quad, and notice that @ stock its 1066mhz, I was going to get myself some 2x2GB 800mhz OCZ stuff that is on offer at the moment, although if I put it straight in all at stock speed in my unit, would that mean that the RAM is overclocked already ?
As the RAM is running at 800mhz and the CPU at 1066mhz ?

Also i've heard about RAM ratio 1:1 and 1:2 ??

In regards to CPU, i get about the FSB is double your clock speed etc etc, although ...........

Could someone perhaps explain this please, as i understand 1:1 is where the RAM is running at the same speed as you CPU, and 1:2 is where your CPU is running at one speed, and your Ram ..... well ........ slower ?

Where would you find the RATIO anyway? at the moment i've got an old Asus Nforce 2 board, and i cannot see anything in the BIOS relating to that, apart from memory frequency and it going from 100% to 200 %

I do plan to OC my new kit when i get it, but would like to further understand the above points first ?

Thanks a bunch :)
 
Intel Core 2 CPUs use quad pumped bus, actual FSB of your 1066 Mhz CPU is 266 Mhz.

DDR is effective of double actual, the actual for 800 Mhz DDR2 is 400 Mhz.

The multiplier for a Q6600 is 9x (E6600 is the dual core, note the Q or E), 266 x9 is nearly 2400 Mhz or 2.4 Ghz.

A 1:1 ratio with the memory maximum of 400 Mhz is 400 x 9 or 3.6 Ghz. This is how far you can overclock a Q6600 without overclocking 800 Mhz RAM (otherwise known as PC2-6400 DDR2).
 
Intel® Core™2 Quad Q6600

9x Multi
266MHz FSB

9x266=2394 (2.4GHz approx)

So to just make the Q6600 run at it's stock speed you would need at least DDR2-533 (PC2-4200), however using DDR2-533 wouldn't allow you to overclock the CPU without also overclocking the memory (PC2-4200 is speced to run at 266MHz/DDR2-533), however the system would be held back by the slower ram as even though the chips GHz speed is derived from the FSB (i.e 9x266) once the data leaves the chip and travels via the Northbridge it is quad-pumped and becomes what is known as the System Bus.

266MHz FSB x4 = 1066MHz System Bus

In an ideal world you would want your memory speed to match the System Bus speed, in the example above this would indeed be DDR2-1064 (PC2-8500).

The confusion comes because of the variables and the end result effective speeds

i.e DDR2-8500 actually runs at 533MHz but because it is DDR its speed is doubled and effectively runs at 1064MHz

The 266MHz FSB speed is quad-pumped and effectively is running at 1064MHz (System Bus).

I can see how it's all confusing at first but keep reading and the penny should drop sooner or later! it really isn't that easy to explain lol! :D
 
(Whoops my mistake, the Q6600 im on about)

They went through all of this in college some years back, as for my current system running a Barton 3200,the clock speed = 200mhz and multiplier = 11 resulting in 2200 (200 x 11) STOCK. My Ram is 200 mhz (400DDR) (PC3200) so I would imagine that my Ram is not holding back my CPU at stock speed, only if I OC this one, then the Ram get's OC'd with it (not very well mind you, struggles to reach an overclock of an extra 150mhz without crazy temperatures and voltage through the roof, although the Ram is SUPERTALENT :p)

So i guess it is the same principles, apart from nothing needs to be doubled or anything as my Althlon XP is only single core.

So to summarise

The Q6600 with a multiplier of 9x with a FSB of 266 = (2400 clock speed), would require ram that is at least DDR2 533 mhz/PC4200 as the FSB is 266mhz. If I was to OC using that spec, then both CPU and RAM would get Oc'd

Although If I got myself some PC8500/533mhz RAM, then if I Oc'd the Q6600 CPU, I wouldnt start Oc'ing the memory unless, i got up to something like 4.8ghz or something silly as i did 533mhz x 9 as the multiplier ???? as me ram would be 1066mhz DDR2 ???

BTW

If I was to get myself some of that OCZ 4GB PC6400 800mhz Ram thats on offer on OC, I would then still just be overclocking the CPU and not the ram until I got to over 3.6 ghz ? The only reason I would get myself the 1066 Ram would be if I was wanting to run at stock everything and at 1:1 ?

Phew
 
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mazza7282 said:
If I was to get myself some of that OCZ 4GB PC6400 800mhz Ram thats on offer on OC, I would then still just be overclocking the CPU and not the ram until I got to over 3.6 ghz ? The only reason I would get myself the 1066 Ram would be if I was wanting to run at stock everything and at 1:1 ?

Phew
Click to expand...

Only if you use a 9x multiplier. I'm using a x8 multiplier (so OCing my PC6400 RAM to 861MHz) at 3.45GHz because it runs stable at this speed with x8 multiplier (and therefore increased FSB) but doesn't run stable this fast with a x9 multiplier. So if you're going to OC it you might consider that it won't necessarily be stablest at a x9 multiplier so it might be worth getting the faster RAM anyway.
And if anyone knows why it's stabler with faster FSB and lower multiplier, do please post!
(My figures are:
Q6600 @ 3.45GHz on a ASUS P5Q Pro P45
CPU ratio - x8 vs x9
FSB: 430MHz vs 383MHz
RAM: 861MHz vs 800ish (can't remember the exact figure but <861)
CPU voltage: 1.45 vs up to 1.4825)
 
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miniyazz said:
Only if you use a 9x multiplier. I'm using a x8 multiplier (so OCing my PC6400 RAM to 861MHz) at 3.45GHz because it runs stable at this speed with x8 multiplier (and therefore increased FSB) but doesn't run stable this fast with a x9 multiplier. So if you're going to OC it you might consider that it won't necessarily be stablest at a x9 multiplier so it might be worth getting the faster RAM anyway.
And if anyone knows why it's stabler with faster FSB and lower multiplier, do please post!
(My figures are:
Q6600 @ 3.45GHz on a ASUS P5Q Pro P45
CPU ratio - x8 vs x9
FSB: 430MHz vs 383MHz
RAM: 861MHz vs 800ish (can't remember the exact figure but <861)
CPU voltage: 1.45 vs up to 1.4825)
Click to expand...

You have the same CPU/RAM and M/B setup ill be haiving, in that case, in that case, i guess im not all too fussed about 1:1, if I can perhaps achieve an overclock similar to yours or at least 3.0ghz i'd be perfectly happy

quick question, why have you put 430 vs 383 ? etc for the others aswell
Is you CPU ratio x8 vs x9 your multiplier then i imagine ?

Sorry for being dumb
 
mazza7282 said:
You have the same CPU/RAM and M/B setup ill be haiving, in that case, in that case, i guess im not all too fussed about 1:1, if I can perhaps achieve an overclock similar to yours or at least 3.0ghz i'd be perfectly happy

quick question, why have you put 430 vs 383 ? etc for the others aswell
Is you CPU ratio x8 vs x9 your multiplier then i imagine ?

Sorry for being dumb
Click to expand...

Oops maybe that wasn't as clear as I'd hoped. The second column of figures (after the vs) is my (failed) attempt at overclocking to 3.45GHz with the CPU multiplier at x9.
The first column of figures (before the vs) is my (successful) attempt at overclocking to 3.45GHz with the CPU multiplier at x8. Thus, I had to raise my FSB speed to 430MHz in column 1 to compensate for the lower CPU multiplier. Simple maths - 430x8 = 3.45GHz, 383x9 = 3.45GHz! Does that clear it up a little?

You should have no difficulty at all with 3GHz overclock, in fact you wouldn't even need to go into the BIOS! This mobo comes with an ASUS overclocking program that runs in Windows and could handle a 25% OC for me, up to 3GHz!
 
ahh that makes more sence thanks a lot

I think I have got this informationm sorted out in me head now, although it would be well jumbled up if i was to tell someone else what you guys have told me (apart from copying and pasting lol)

I'd probably shoot off into the Bios though to see how far i can get it to go

p.s I know this is a M/B question, but is that 5 second linux start up option on this M/B any good ?
Thanks
 
mazza7282 said:
ahh that makes more sence thanks a lot

I think I have got this informationm sorted out in me head now, although it would be well jumbled up if i was to tell someone else what you guys have told me (apart from copying and pasting lol)

I'd probably shoot off into the Bios though to see how far i can get it to go

p.s I know this is a M/B question, but is that 5 second linux start up option on this M/B any good ?
Thanks
Click to expand...

Sorry, I couldn't tell you as I've never used it! I've heard 5 seconds is a bit optimistic, but since I rarely reboot my pc, I never bothered looking at it and I'm not even sure it's installed.

What cooling setup are you planning on getting? I'm currently using an Arctic Cooling Freezer 7 Pro, but I've heard there are better coolers out there for the price. You should be able to get up to 3GHz on the stock heatsink, though I'm not such a fan of the stock fan (haha :(), it gets rubbish temperatures and is generally a bit poo. So until I got the AC Freezer, I took the Intel fan off and superglued a stock AMD one from my previous build to the Intel heatsink, temperatures came right down lol!
 
miniyazz said:
Sorry, I couldn't tell you as I've never used it! I've heard 5 seconds is a bit optimistic, but since I rarely reboot my pc, I never bothered looking at it and I'm not even sure it's installed.

What cooling setup are you planning on getting? I'm currently using an Arctic Cooling Freezer 7 Pro, but I've heard there are better coolers out there for the price. You should be able to get up to 3GHz on the stock heatsink, though I'm not such a fan of the stock fan (haha :(), it gets rubbish temperatures and is generally a bit poo. So until I got the AC Freezer, I took the Intel fan off and superglued a stock AMD one from my previous build to the Intel heatsink, temperatures came right down lol!
Click to expand...

I will also be using the Artic freezer pro on my setup aswell, (dont have a coolermaster cosmos rc1000 by any chance do you lol

I once superglued one once to a project I was building, very affective

The stock fan will be put in the drawer with the rest of me rubbish :
 
mazza7282 said:
I will also be using the Artic freezer pro on my setup aswell, (dont have a coolermaster cosmos rc1000 by any chance do you lol

I once superglued one once to a project I was building, very affective

The stock fan will be put in the drawer with the rest of me rubbish :
Click to expand...

Heh no coolermaster for me! I went for an Antec p182. Designed more for silence than for airflow, so chances are you'll get a better clock than me. Anyway, I'm down to 3.3GHz until I do some more video encoding or maybe a bit of Crysis; this seems to be the sweet spot at which I can have all cores maxed out with all case fans on minimum. Upping it to 3.45 makes my PC sound like it's about to take off, those Antec fans aren't quiet when they're on full!
 
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