Corsair RAM Query

I will soon be overclocking my p4 1.6a to ~2.4. I have 512mb of Corsair pc3000.

I've heard about overclocking RAM, will i need to?
If so how?

also will the RAM handle 2.6 DRAM volts OK?


deks..

deks WELCOME to the forums!

If your overclocking your processor you will have to raise the FSB so your ram will also be running faster. Your Corsair will be able to overclock very well without upping the voltage much. 2.7v for your ram is ok and some even go over 3v. 2.7 is always safe since its within the manufacturers tolerance. If you give us your system specs we can help you out a lot more getting that thing up to speed.

If you have the right motherboard you can run your memory at 166 or 200mhz without overclocking the cpu.

On these boards you just set the memory to cpu ratio in the bios.

But having a 1.6a and not overclocking it might be considered a crime

Hey check this DDR pc3000 and pc3200 shootout

Its to bad they didnt include Mushkin as Mushkin will go head to head with Corsair pc3000 and pc3200


http://www.hardwareluxx.de/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic&f=6&t=000015

Wow they used almost the same motherboard as I have and got almost the exact results. My Mushkin PC3000 on an Asus P4S333-M maxes out at 220 MHz 2,5-2-3-6-2. Remember this is only with 2.5v going to the ram. If you have ram voltage adjustments on your board it will let you go even faster.

Overclock RAM

So the only way to overclock RAM is by Rasing the FBS?
And by doing that you can only go so high then you have to raise the Voltage right. I hope i am getting that right lol.

The only way you can oc an Intel cpu is by raising the fsb. But this also affects the mobo, cause the fsb is the speed of the signal the mobo communicates with the other components with. So when raising the fsb you oc the whole system, that includes Video Card (AGP Port on most new systems) Sound card (PCI), network card (PCI), RAM, HDD's +++

But then we have a smart thing called dividers.

AGP =2/3
PCI =1/3 or 1/4 or is locked
RAM =varies

So when running the fsb at 100mhz, the AGP bus is running 66mhz, and the PCI (with a 1/3 divider) at 33mhz. If the RAM divider is 1/1 the RAM will run 100mhz. But to 1,6GHZ CPU to 2,4GHZ, you will have to raise the fsb cause the Intel has a locked divider (in you're case it's 16, because of "16" 00 mhz (usually fsb on intel systems are 100mhz)).

So let's take you're example:

To oc the 1,6@2,4 you will need this raise

x=2400/16
x=150

Now, "x" is your fsb. You will be needed to run at 150mhz fsb to reach 2,4GHZ. But what does this have to say about the RAM, PCI bus, and AGP bus??

As said, the AGP divider is 2/3, and PCI is 1/3. But when you reach the speed of 133mhz fsb, most mobos changes the PCI divider to 1/4. But this only goes from 0-133mhz, each raise above that will be with 1/3 divider. Let's say the RAM divider is still 1/1.

Then these numbers are what you will get:

AGP = (133*2/4)+((150-133)*2/3)
AGP = 78mhz
PCI = (133*1/4)+((150-133)*1/3)
PCI = 39mhz
RAM = 150mhz

This is why sound cards (PCI) and Video cards (PCI) might limit the oc. But you're ram is only running 150mhz!! While pc3000 should run 187,5mhz....

So you change the RAM divider to f. instance 5/4, and then you get

RAM speed=150*5/4
RAM speed=187,5mhz (I was not sure this was gonna hit this good )

So you can change the dividers for oc the RAM. To reach those speeds you might need to upper the votage a bit, yes.

IMPORTANT NOTE:

Not all mobo's have these dividers, these are all in general. They might not fit all mobos. Some Epox cards have a locked PCI bus, I'm not sure about what other cards that have these.

elysium

Thanks elysium,

Great help
My system is at current:

p4 1.6A
Abit BD7-RAID
Thermaltake Volcano 7+
512Mb Corsair PC3000 DDR
WD 80Gb HDD 8Mb cache
40x32x12x CDR
16x DVD
GeForce 2 MX200
On Board Sound

I'm going to lock PCI to 33Mhz
If I up my FSB to 150 this will run my AGP at 100Mhz. Do you think the GeForce 2 MX200 will handle it...

Also you say by changing the RAM divider to 5/4 it will up the RAM speed to 187.5Mhz. Do you think DRAM voltage of 2.6 should be sufficient??


again Thanks,
deks..

I'm not sure about the GeForce 2 capable of 100mhz bus, but you're ram is supposed to run 187,5mhz at 2,5memcore, so I supposse that would work. If you up it to 2,7 you might be able to set a higher divider for the ram, giving better speeds

Do that card have a locked pci bus??

elysium

My BIOS has the option to lock the PCI.

My GeForce 2 is on the AGP slot.