DDR2 VS DDR1?

[gate1975mlm]

What would be the Benefits of using DDR2 677 over DDR1 400?

 

[TheStu]

DDR2 677 (or is it 667?) has higher bandwidth obviously but DDR 400 has much lower latencies... and DDR is used on A64 and DDr2 is used on all the new Intel stuff

As far as benefits.. I'm not sure if there are any

 

[Aenslead]

Higher latencies on DDR2 keeps it from performing better than low latency lower-bandwith DDR; Also, DDR2 533 and 667 are practically useless, since inspite P4 being memory bandwith starved, pretty much fills it up with Dual Channel DDR400 (6.4Gb/s for 800Mhz FSB); DDR2 533 only gives a slight boost when using P4 EE (extremely expensive) w/1066Mhz FSB. In other words: nobody needs it.

And that's all I have to say about that.

 

[Duvie]

Aenslead is right above...DDR2 with a 800mhz prescott would be a waste since theoretical bandwidth on the 800fsb chips is only 6.4gb/s....Basically the DDR2 is good for the 1066fsb P4-EE chips and overclockers who raise the bus and need some ram to hit those speeds...It appears it is needed for the bandwidth the dual cores need, but then again they have starved it with a shared memory bus anyways....

 

[Leper Messiah]

DDR2 is a dog technology. Who cares if you can hit DDR800 when your latency values are 5-5-5-15? Why do you think the GPU companies went from ddr2 to ddr3 so quickly?

 

[Bateluer]

To be fair, DDR2 modules with lower timings do exist. Here, for example. Granted, its still much higher than the 2-2-2-5 you can get on a DDR400 module. AMD has DDR2 in their roadmap as well, but hopefully DDR3 will be close behind it. Or better yet, fit in the same slot.

 

[Leper Messiah]

yeah, buts that with 533 modules. BH-5 can do that with 2-2-2-5 settings. To get the PC6400, 5-5-5-15 is about the best you can do.

 

[Aenslead]

When AMD releases their M2 socket and 1200Mhz FSB (300Mhz) then there will be some use for DDR2's high bandwith. But until then (Q1 06), DDR2 is pretty much... well... useless; sort of what Rambus memory was some time ago with i820/i850/e chipsets: expensive and with no performance bennefit.

 

[Suspicious-Teach8788]

Yea and when OCZ VX is hitting 530 @ 2-2-2, then your DDR2 looks like crap. 5-5-5-15 is crap. Lower timings all the way is THE WIN.

 

[Acanthus]

The performance difference between DDR 400 3-4-4-8 ($40 for 512MB garbage ram) and Top of the line DDR2-800 (you dont even want to know the price) is about 5% on the pentium 4.

 

[imported_michaelpatrick33]

It will be interesting to see how the AMD dualcores do with the integrated memory controller since they are not bandwidth starved. I wonder if they will get better performance at 6.4Ghrtz/s memory because of that?

 

[RichUK]

Originally posted by: L3p3rM355i4h
DDR2 is a dog technology. Who cares if you can hit DDR800 when your latency values are 5-5-5-15? Why do you think the GPU companies went from ddr2 to ddr3 so quickly?

There is no such thing as DDR3, GFX cards use GDDR3 its modified DDR2 to run higher bandwidth.

 

[Leper Messiah]

hm. I know I heard some speculation a couple of months ago that AMD was going to skip DDR2 all together and migrate directly to DDR3. The fact still remains that DDR2 is t3h suxx0rz.

 

[RichUK]

yes i have heard the speculation aswell, i am familiar with how DDR and DDR2 works, but DDR3 (the proposed successor) i havent seen any info on and am interested on what technologies this will run.... at the moment as we all know DDR2 is made for bandwidth, as it is in its infancy and the tech to reduce latency is not yet available and only suites the need of intels EE chips...

The question is what will DDR3 bring?

lower latency as apposed to DDR2?
Higher bandwidth?
Cooler temps/lower volts?

i would certainly like to know.

 

[Leper Messiah]

well, we can speculate based upon what they did with GDDR3. It runs alot cooler per mhz, and has a lower ns rating, so that would translate to lower latencies, I guess.

 

[Aenslead]

AMD Roadmaps still show DDR2 for Q1/2 '06; That's when its estimated that more than 50% of memory sold on the market is DDR2 due to Intel plataforms.

Let us, however, remember transtition from SDRAM PC133 to DDR266: the performance gains on the AMD plataform where also pretty much negliable, but the technology itself was necesarry. Such will be the need for DDR2.

 

[milkrocks]

It seems interesting that when a new RAM technology strives purely for bandwidth and not latency that it seems to be uneffective overall. RDRAM bandwidth was huge compared to SDRAM of the time. DDR2 Bandwidth is much higher than current DDR.

Latency should be a bigger piece of the equation. A machine with lower bandwidth memory that runs at lower latencies will often perform better in many everday apps. By this time next year we may see DDR2 will far lower latencies than we do now.

There are other aspects of DDR2 that are beneficial - lower power requirements and less heat. All things being equal a DDR2 module would be prefered to a DDR1 chip (same latency and frequency).

When AMD goes to a 300mhz FSB it is likely that DDR1 will not make the transition. By that time DDR2 may be a lot faster than it is today.

 

[Acanthus]

Originally posted by: milkrocks
It seems interesting that when a new RAM technology strives purely for bandwidth and not latency that it seems to be uneffective overall. RDRAM bandwidth was huge compared to SDRAM of the time. DDR2 Bandwidth is much higher than current DDR.

Latency should be a bigger piece of the equation. A machine with lower bandwidth memory that runs at lower latencies will often perform better in many everday apps. By this time next year we may see DDR2 will far lower latencies than we do now.

There are other aspects of DDR2 that are beneficial - lower power requirements and less heat. All things being equal a DDR2 module would be prefered to a DDR1 chip (same latency and frequency).

When AMD goes to a 300mhz FSB it is likely that DDR1 will not make the transition. By that time DDR2 may be a lot faster than it is today.

XDR and DDR2/3 will be very important in the near future when dual and multicores hit the market, you will now have more than one core fighting for the same bandwidth.

 

[Acanthus]

Originally posted by: RichUK
yes i have heard the speculation aswell, i am familiar with how DDR and DDR2 works, but DDR3 (the proposed successor) i havent seen any info on and am interested on what technologies this will run.... at the moment as we all know DDR2 is made for bandwidth, as it is in its infancy and the tech to reduce latency is not yet available and only suites the need of intels EE chips...

The question is what will DDR3 bring?

lower latency as apposed to DDR2?
Higher bandwidth?
Cooler temps/lower volts?

i would certainly like to know.

Higher latency than DDR2
Higher bandwidth than DDR2
Cooler temps and lower volts due to smaller process

Its more evolutionary than revolutionary, i dont know why its being kicked around as better than DDRII when its only going to magnify the problems.

 

[akugami]

I was under the impression that DDR3 would be high bandwith but with lower latencies than DDR2 and even lower voltages than DDR2. Basically DDR2 on steriods while running at lower voltages. I know it is being kicked around as the RAM to use in notebooks post 2006 due to it's low voltage requirements. This will help battery life. I believe DDR1 is 2.5v, DDR2 is 1.8v, DDR3 is 1.5v.

 

[Duvie]

http://www.lostcircuits.com/memory/ddr3/6.shtml

I found this and it has a bit more to dso with GDDR3 but it should be identical.....The DDR3 will be uch lower power which will be a boom for laptop capabilities, but it is unsure from some of the other signal enhancements of GDDR3 whether cas latencies will be better...They may not be anything similar as the way we know them now...

 

[Duvie]

Originally posted by: Acanthus

Originally posted by: RichUK
yes i have heard the speculation aswell, i am familiar with how DDR and DDR2 works, but DDR3 (the proposed successor) i havent seen any info on and am interested on what technologies this will run.... at the moment as we all know DDR2 is made for bandwidth, as it is in its infancy and the tech to reduce latency is not yet available and only suites the need of intels EE chips...

The question is what will DDR3 bring?

lower latency as apposed to DDR2?
Higher bandwidth?
Cooler temps/lower volts?

i would certainly like to know.

Higher latency than DDR2
Higher bandwidth than DDR2
Cooler temps and lower volts due to smaller process

Its more evolutionary than revolutionary, i dont know why its being kicked around as better than DDRII when its only going to magnify the problems.

http://www.jedex.org/images/pdf/reza_hynix_keynote.pdf

This suggest maybe that is not so....

 

[Insomniak]

Like more bandwidth is even needed or something. DC is already overkill for most chips.

 

[Duvie]

Originally posted by: Insomniak
Like more bandwidth is even needed or something. DC is already overkill for most chips.

For AMD chips not necessarily P4's and dual core P4's.....

 

[hippotautamus]

Correct me if I'm wrong, but aren't Intel chips far more bandwidth choked than AMD CPUs are, thanks to the slower FSB?