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View Full Version : WTF? DDR-II for system RAM?!?


ricercar
04-17-05, 02:44 AM
So DDR-II is coming for system memory ... and I simply do not understand.

I know that DDR-II has greater bandwidth potential at the cost of higher latency. So, DDR-II has frequency headroom for nextgen gighertz CPUs ... when they eventually arrive. AMD says they will not support DDR-II until 2006, and Intel will remain stagnant in CPU clockspeed until they can implement the IP they traded NVIDIA for the P4 FSB license--anywhere from 6-18 months from the day they inked that deal, depending on how much Intel had already infringed on the NVIDIA patents.

Yet DDR-II on graphics card was a complete bust: expensive, and way too hot for the performance. NVIDIA and ATI moved directly to DDR3 without much of a stop at DDR-II. Anyone remember the FX 5700/5800 or 9800Pro models with DDR-II? You can't replace the factory RAM cooler with anything except a waterblock, because DDR-II RAMs get too hot. Consumer aftermarket aircooled RAMsinks don't have anough radiating surface to keep DDR-II memories within spec--at least none I tried.

So WTF is this with system RAMs going DDR-II? With economy of scale the expense differential of course will disappear, but it still seems like using DDR-II as main memory (instead of DDR3) is beneficial only to the aftermarket cooling scene, because system memory module coolers will actually become necessary.

Muppet
04-17-05, 03:45 AM
From what i've seen you've been able to buy DDR 2 memory for a little while now, well at least i can in NZ and we are so far away and new technology takes a while to reach us

Burnt_Ram
04-17-05, 10:40 AM
From what i've seen you've been able to buy DDR 2 memory for a little while now, well at least i can in NZ and we are so far away and new technology takes a while to reach us
i can buy it here in Canada aswell. its even a bit cheaper ! only for the Intel mobo's i think tho ?

jolle
04-17-05, 11:43 AM
yeah the P4 is the only platform using it atm..
Which isnt that strange since P4 has been going with Bandwidth over Latancy for a while now..

AMD on the other hand went the other way, reduced latancy even further by putting the memory controller on the CPU instead of in the mobo chipset with the A64.
So DDR2 has to scale a bit more before the bandwidth can make up for the latancy, before AMD starts using it..
Clock per clock DDR2 is slower due to the latancy.

With gaming and such Latancy seems to often be a bit more important then high bandwidth, since you got alot of smaller chunks of less predictable data being sent around, while high bandwidth is more suitable for streaming stuff, like video, larger predictable chunks of data..

GDDR3 is pretty much DDR2 with some modifications to be better suited with graphics cards, I think..
They work in a similar way, GDDR3 is ofcource cooler and has some extra features, but I think they are basicly the same other then that..
I think todays DDR2 modules for PC is alot cooler then the earlier modules used on FX5800 that ran really hot, manufacturing process is a bit more matured and such, might have incorporated some of the tweaks in GDDR3 perhaps..
not sure, havent followed up on that alot, im sure there are a slew of reviews out featuring DDR2 on P4 platforms, its not really all that new anymore.

Gator
04-19-05, 09:13 AM
As mentioned, I think the DDR2 sticks intended for P4 are a little different from the DDR2 used on earlier video cards. And P4 can benefit from DDR2 because P4 is so bandwidth hungry. I don't see a reason for A64 to ever use DDR2 though.

So far as I know GDDR3 is specifically intended for video cards, so I wouldn't expect to see it in stick/module form anytime soon.
(wack)

sabersix1
04-19-05, 10:48 AM
Corsair Was just Named a Launch Partner for the Nvidia Nforce 4 SLI Intel Edition, and Since the Board will take all Intel Socket 775 (Celeron 3xx@533FSB, Prescott 5xx,6xx,7xx @ 800FSB, and the Intel Extreme Editions 3.46EE and 3.73EE @1066FSB, Corsair came out with The Fastest DDR2 to Date. The Corsair CM2X512A-5400UL 675MHz with 3-2-2-7-1T Timings. And The CM2X512A-6400 800MHz @ 5-5-5-12-2T. Read more at: http://corsairmemory.com/corsair/nvidia_index.html . I have been Using 2 GB's Kingston Hyper X PC2 5400 675MHz at 4-4-4-10-4 which is stock peed and they run my Rig Great. DDR2 is here to stay and the ony reason AMD wont add it to thier Spec is they can't see the Forest for the Trees. In other words AMD says it would be to costly to get Manufactures to retool the lines for DDR2, but they already have for the Intel/Nvidia Boards. Anyways DDR2 is Great and you can find them at any ONLINE Computer Store. Keep It Cool. JKohl

ViN86
04-19-05, 11:33 AM
only thing i can see going for DDRII is that the speed is gonna get so fast that the latency wont mean squat.

jolle
04-19-05, 11:34 AM
Well AMD will go DDR2 sooner or later, but they have to become faster before they will yield any performance benefits on the A64 since the increased latancy will cost more performance then it does for the P4 that doesnt have very low latancy to begin with..

And with the A64 featuring a on-die memory controller the support wont come until a few cores into the future prolly..

If you look at this comparison of DDR400 and DDR2 533. (I know its not the fastest DDR2 on the market)
http://www.overclockercafe.com/Articles/DDR_vs_DDR2/pg_3.htm
You se that even tho the higher clock, there arent any huge gains with it, and that is on the P4, the A64 has alot lower latancy and might have been a bit slower with the DDR2..
So I think they are simply holding out until the speed is ramped up a bit, and a nice side effect for that is that the production of DDR2 will be increased so prices should be lower by that time..
Q1 2006 if this roadmap is anything to go by:
http://www.vr-zone.com/?i=1829&s=1


Article about DDR, DDR2 and GDDR2&3 and their differances for anyone interested..
http://www.lostcircuits.com/memory/ddr3/

thanosAIAS
04-20-05, 01:27 AM
i see DDR3 just around the corner and without the limitations of DDR2...


...and lets not forget RAMBUS 2 ...as in RAMBO 2 :p

TierMann
04-20-05, 05:14 AM
http://www.nvnews.net/vbulletin/showthread.php?t=49001

ragejg
04-20-05, 09:16 AM
/moved

;)

Viral
04-20-05, 07:49 PM
So DDR-II is coming for system memory ... and I simply do not understand.

I know that DDR-II has greater bandwidth potential at the cost of higher latency. So, DDR-II has frequency headroom for nextgen gighertz CPUs ... when they eventually arrive. AMD says they will not support DDR-II until 2006, and Intel will remain stagnant in CPU clockspeed until they can implement the IP they traded NVIDIA for the P4 FSB license--anywhere from 6-18 months from the day they inked that deal, depending on how much Intel had already infringed on the NVIDIA patents.

Yet DDR-II on graphics card was a complete bust: expensive, and way too hot for the performance. NVIDIA and ATI moved directly to DDR3 without much of a stop at DDR-II. Anyone remember the FX 5700/5800 or 9800Pro models with DDR-II? You can't replace the factory RAM cooler with anything except a waterblock, because DDR-II RAMs get too hot. Consumer aftermarket aircooled RAMsinks don't have anough radiating surface to keep DDR-II memories within spec--at least none I tried.

So WTF is this with system RAMs going DDR-II? With economy of scale the expense differential of course will disappear, but it still seems like using DDR-II as main memory (instead of DDR3) is beneficial only to the aftermarket cooling scene, because system memory module coolers will actually become necessary.

G-DDR3 is not DDR3. It is based off DDR-II. So there is still hope for DDR-II.

I agree with what you are saying, but corsair just bought out DDR-II with very good timings. AMD could release a new socket that supports DDR-II 667 now and have a good performance increase IMO. Still, that would leave too many people out in the cold... unless they kept S939 as the DDR platform and released CPU's simuletaneously. Doing that is risky stuff, though, they would need to be right up there with the demand and not overshoot either.

superklye
04-20-05, 08:28 PM
G-DDR3 is not DDR3. It is based off DDR-II. So there is still hope for DDR-II.

I agree with what you are saying, but corsair just bought out DDR-II with very good timings. AMD could release a new socket that supports DDR-II 667 now and have a good performance increase IMO. Still, that would leave too many people out in the cold... unless they kept S939 as the DDR platform and released CPU's simuletaneously. Doing that is risky stuff, though, they would need to be right up there with the demand and not overshoot either.
nForce5

JoKeRr
04-20-05, 08:40 PM
I particularly don't like that benchmark comparison. They only used a 2.8ghz prescott, that's wayy to slow to demostrate the difference. P4 scales better with higher bandwidth, and that's why 1:1 was soo popular with 875P and 865PE chipset. Hell even a northwood can run over 2.8ghz easy, why didn't they toss in a 3.6ghz instead??


Well AMD will go DDR2 sooner or later, but they have to become faster before they will yield any performance benefits on the A64 since the increased latancy will cost more performance then it does for the P4 that doesnt have very low latancy to begin with..

And with the A64 featuring a on-die memory controller the support wont come until a few cores into the future prolly..

If you look at this comparison of DDR400 and DDR2 533. (I know its not the fastest DDR2 on the market)
http://www.overclockercafe.com/Articles/DDR_vs_DDR2/pg_3.htm
You se that even tho the higher clock, there arent any huge gains with it, and that is on the P4, the A64 has alot lower latancy and might have been a bit slower with the DDR2..
So I think they are simply holding out until the speed is ramped up a bit, and a nice side effect for that is that the production of DDR2 will be increased so prices should be lower by that time..
Q1 2006 if this roadmap is anything to go by:
http://www.vr-zone.com/?i=1829&s=1


Article about DDR, DDR2 and GDDR2&3 and their differances for anyone interested..
http://www.lostcircuits.com/memory/ddr3/

Viral
04-20-05, 11:24 PM
That, and the memory wasn't running 1:1 with the FSB. This is the main reason DDR-II is looking lackluster right now. If Intel had upped their FSB with the introduction of it results would have been better, but now they have gone cache crazy and it wouldn't make much of a noticable difference anymore. ;\

JoKeRr
04-20-05, 11:51 PM
That, and the memory wasn't running 1:1 with the FSB. This is the main reason DDR-II is looking lackluster right now. If Intel had upped their FSB with the introduction of it results would have been better, but now they have gone cache crazy and it wouldn't make much of a noticable difference anymore. ;\

I wouldn't mind getting more cache but the fact that they're also giving L2 cache even higher latency doesn't really help either. One of the reason why Dothan performs soo well is b/c of the ultra low latency L2 cache.