DDRII Facts

This is a very quick and simple thread that will educate you about DDRII.

First;
DDRII is 100% backwards compatible with DDR1. DDRII simply uses 0.09 Micron technology along with large taller dimm specs.

DDRI technology was limited to a maximum memory size of 2GB Dimms (1GB on each side). DDRII on the other hand can handle four times the amount of memory, up to 4GB of each side meaning you could potentially have a total of 8GB of one stick of memory!).

DDRII can operate at 2.5V or 1.8V on the fly. The way DDRII works is, you must lower the voltage to use frequencies behond 333MHz according to Jedec. The reason for this is simple, DDRII 533 is rated to run 533MHz at 1.8V, not 2Volts or 2.5Volts. If you were to run that memory at 2.5V, chances are youd roast your new memory.

Currently, the only way to run high speeds on DDRII with old ddr1 boards is to volt mod your memory control so that it brings down the voltage to 1.8-1.9volts.

Here is the good news, DDRII is HERE. By this time next year, all PCs will have DDRII 533 in them. DDRII 533 is an official spec by Jedec which will launch Q1 2003. This memory will cost simular to DDR1 but with a 200MHz boost from the 333MHz (PC2700 spec from Jedec).

As of January this year, Micron will have started to ship DDRII533 to consumers.

DDRII533 Spec states two voltage settings;

2.5V at 333MHz

1.8V at 400MHz

1.8V at 533MHz

At 533MHz, DDRII memory runs so cool that you wont even notice any temperture changes even by touch.

There you have it, simple and easy to understand. Now, we gotta wait untill like February!


OC-Master

Wow, Im no memory expert techy...but all that sounded pretty awesome....backward compatible would be meaning if I got an nforce2 , I could use DDRII in it ?

*runs*

Sounds like an overclockers dream to me. Running ram at 533mhz, and then cranking the voltage from 1.8 to 2.0! Hahahaha....

I see 3dmark and Sandra scores going through the roof here in notime

seems weird how the speed slows when more voltage is applied...

Digital

So could you use ddr-II in a nforce2 board

So in otherwords, since it is backwards compatible. You should be able to do ALL speeds to 533 at low voltage. Meaning you wouldn't need to cool your ram anymore if you can only get 380 out of it (because of your CPU). Which in-turn means LESS heat in the case!!! So technically wouldn't that lower the temp of the northbridge?

NyTe said:

...So technically wouldn't that lower the temp of the northbridge?

Click to expand...

probally not, the northbridge does a lot more than just a memory controller.

Digital

Basically, the easiest way to understand is wattage = Heat!

Just like a CPU, the more MHz you use, the less amount of voltage you wanna be able to use. EX: K6-2 500MHz uses 2.2V where as a 1GHz Athlon uses only 1.75v. The Athlon is clearly the win win situation.

Memory works exactly the same way. This is why we havnt seen memory speeds behond PC3500 spec. The reason for this is, ask anyone who has PC3500 who runs there memory at 434MHz. They will tell you that memory gets very warm, if not HOT!


OC-Master

So DDRII may actually be as fast as pc1066 RDRAM is now? )

That's nice if it runs cooler though...

I believe it's the smaller die size allows the silicon to run at a lower voltage.

As far as I got it, the DDR II is going to be bigger (longer) then the DDR I, so how would it be backwards compatible ?
As I saw on the QBM (Quad Band memory) Site and I quote: "Both DDR I and QBM DIMMs fit into standard 184-pin connectors unlike the 240-pin DDR II which is not backward compatible with DDR I."
if anyone wants the link Here it is QBM FAQ.
if anyone got the answer what is going on I will be rreally happy to hear it.

amd_builder said:

So DDRII may actually be as fast as pc1066 RDRAM is now? )

That's nice if it runs cooler though...

Click to expand...

it takes ddr 448 to equal 1066 speeds.

uhhh let`s pretend that we can actually lower the voltage of memory but... who can take his athlon fsb to 533??? i think p4 is the winner here, am i wrong??

Darkseid said:

uhhh let`s pretend that we can actually lower the voltage of memory but... who can take his athlon fsb to 533??? i think p4 is the winner here, am i wrong??

Click to expand...

Well,

nForce2 supports aggressive memory configurations of up to 1GHz using standard 184-pin technology.

ASUS's nForce2 board with the latest bios allows for FSB speeds up to 500MHz and there is an option that will make the ram run anywhere from 105~200% of the FSB. At 150%, that would be 750MHz if I was running a 500MHz FSB.

I expect tha most people who have there nForce2 at 400MHz FSB will use the 135% memory running option so there memory can run at a full blown 533MHz.


OC-Master

OC-Master said:

Memory works exactly the same way. This is why we havnt seen memory speeds behond PC3500 spec. The reason for this is, ask anyone who has PC3500 who runs there memory at 434MHz. They will tell you that memory gets very warm, if not HOT!

OC-Master

Click to expand...

I have a Corsair XMS3200 C2 (PC3200) and I run it at 255MHz(510MHz DDR)......he,he,he....

Well, AMD systems won't see a huge change at stock speeds, most likely just a tiny increase.

Once you get your ram to equal the fsb in an AMD system, you're pretty much done, because the extra memory mhz will mean just about nothing. So to take advantage of all that bandwidth, the fsb would have to be cranked up to INSANE speeds, speeds that they most likely won't have dividers to keep the PCI/AGP at default or close to default.

DDRII running at 533mhz would mean an AMD's fsb would have to be at 266mhz!! Unless you have the dividers to go that high, and have your processor unlocked, you can watch your hard drive painfully die from the overclock. Now the new 333fsb's will help out some, but there's still some way to go to bridge the gap.

Intel's will finally have their bandwidth filled, but they're next move is to a 666mhz (muhahahaha, bill gate's number) bus............

Onwards and upwards..........

Edit - Oh yeah, BTW, voltage will drop when chips go to a smaller process......kinda like how a smaller pipe flows less water, but in a computer case this is better......whatever. And DDRII will use a .09 process, technically qualifying as NANOTECHNOLOGY! (oooooooh)

Stumpjumper5200 said:

Well, AMD systems won't see a huge change at stock speeds, most likely just a tiny increase.

Once you get your ram to equal the fsb in an AMD system, you're pretty much done, because the extra memory mhz will mean just about nothing. So to take advantage of all that bandwidth, the fsb would have to be cranked up to INSANE speeds, speeds that they most likely won't have dividers to keep the PCI/AGP at default or close to default.

DDRII running at 533mhz would mean an AMD's fsb would have to be at 266mhz!! Unless you have the dividers to go that high, and have your processor unlocked, you can watch your hard drive painfully die from the overclock. Now the new 333fsb's will help out some, but there's still some way to go to bridge the gap.

Intel's will finally have their bandwidth filled, but they're next move is to a 666mhz (muhahahaha, bill gate's number) bus............

Onwards and upwards..........

Edit - Oh yeah, BTW, voltage will drop when chips go to a smaller process......kinda like how a smaller pipe flows less water, but in a computer case this is better......whatever. And DDRII will use a .09 process, technically qualifying as NANOTECHNOLOGY! (oooooooh)

Click to expand...

Nforce 2 motherboards have PCI/AGP locks in case you didn't realize.

Oh yeah...........

In that case, sweet

Just out of curiosity, how do those locks work? Is it like a continuously variable divider? And are there any P4 boards out there with PCI/AGP locks?

P4 boards have had locked PCI dividers for quite some time. This is why we are all so happy about the nForce2 boards. It is about damned time !

The locks work in that you can have whatever FSB you want and the PCI will stay at 33 mhz and the AGP will stay at 66 mhz no matter what. Overclocked AMD's are gonna be sweet. Major performance if you pump the FSB up and are using memory in the dual ddr configuration.