Why would anyone want DDR2, anyways?

[Aenslead]

I just got an Intel i915PGNL motherboard, that uses DDR400 memory. Works pretty much ok. Crispy performance, so everything is nice. A little picky with memory modules (had to use Kingston, otherwise the other cheapo modules would be detected as DDR333 and cause some problems).

Anyways, I was curious on what I was mising, due to DDR II memory and 925x chipset... and I searched around at Anandtech, and found something pretty nasty.

http://www.anandtech.com/mb/showdoc.aspx?i=2293&p=29

I simply nodded and sighed.

DDR II is quite the fiasco, I'm afraid. Why the push for such technology then? Besides, Sandra shows that P4 can't even use 60% of their total bandwith, whereas the Athlon 64 skt754 uses almost 95% of its available bandwith, and the skt939 uses around 80%, no?

Why would I want to get a DDR II motherboard/processor? Is there any advantage at all?

 

[StormRider]

I have a ton of DDR memory so I would prefer that DDR2 won't make it big.

 

[AnandThenMan]

DDR2 is designed to scale to much higher frequencies than DDR, hence in theory making it more future proof. Only when AMD goes to DDR2 will we start to see the full potential (or lack thereof) of DDR2.

 

[Azkarr]

An article from an interview with OCZ on AT said that DDR will be around for some time. I'll be able to hang on to my S939 PCI-E board for about 1 more year.

 

[exar333]

DDR2 is nice in power consumption tho, especially for laptops...lower volatge=lower power usage....thats one advantage.....but i def prefer DDR at the moment....

 

[imported_Kensai]

DDR2-1000.

 

[theMan]

hopefully in the future those latencies will come down.

 

[Peter]

Why the push for DDR2? Combine these facts into a conspiracy theory:

* Intel chipsets are synchronous in that RAM frequency must equal FSB frequency.
* Pentium-4 hugely depends on fast FSB.
* DDR1 cannot safely go past 200 MHz (x2).

So, Intel felt the need to push the FSB to 266 MHz QDR ("1066 MHz" in marketingspeak), thus needed RAM that runs at 266 MHz DDR. Now with few P4 CPUs actually using more than 200 MHz QDR, and DDR2 access latency generally being higher than DDR1, all that users currently get is the lower throughput at a speed that might just as well have been covered with DDR1.

 

[Aenslead]

there is no need whatsoever for the extra bandwith. Pentium 4 cannot even use the existing bandwith in the dual channel configs, and Anand recently tried DDR2 memory runing 1:1 with FSB, and there was no improvement whatsoever on performance.

Why is Intel so interested in using OTHER memory technologies? This is not as bad as Rambust thing, but it is useless still. Anyone remember the i820 chipset, for Pentium 3 with RDRAM? That's how this is.

 

[akugami]

DDR2 even now on laptops make sense, lower voltages means less power consumption means longer battery life. DDR2 is not needed at this time because DDR1 speeds and bandwith are roughly on par with DDR2 except for very high end and select (read: expensive) DDR2 modules.

DDR3 will be with us in about two years. I have no desire to upgrade to DDR2 due to lack of features and benefits over DDR1 at the desktop market. I'll wait for DDR3 for both the desktop and my next laptop. IBM Thinkpad running a P3 still doing ok for light duty. Desktop system still very good.

 

[Peter]

Aenslead: It isn't about using the extra bandwidth, it's about keeping the CPU and RAM frequencies synchronous. "FSB1066" (266 MHz QDR) CPUs requires DDR2-533 (266 MHz DDR) RAM in case there's an Intel northbridge inbetween.

 

[superfly27]

Well, I'm sure I'm the big idiot here. But, if you have a CPU with 1600 MHz bandwidth, aren't you better off with 1600 MHz RAM?

 

[Aenslead]

Originally posted by: Peter
Aenslead: It isn't about using the extra bandwidth, it's about keeping the CPU and RAM frequencies synchronous. "FSB1066" (266 MHz QDR) CPUs requires DDR2-533 (266 MHz DDR) RAM in case there's an Intel northbridge inbetween.

Yes, I agree... but performance wise, where has that taken anyone?

Anand's review of the 1.06Ghz FSB P4EE showed it did not do anything noticeable for real world performance, so obviously, P4's have all the bandwith they could need, no?