DDR 400 Dual Channel or DDR2 800

[murgaan]

Which is "better," dual channel DDR 400 or DDR2 800? (assuming the DDR is lower latency) Keep in mind the FSB is 800MHz.

Part 2: Will DDR2 800 dual channel perform any better than single channel considering the FSB is 800MHz?

Thanks

 

[bamacre]

You need to see which one your motherboard supports.

 

[murgaan]

Well, that's the thing. I haven't bought a motherboard yet. I'm trying to figure out what motherboard/memory combination has the best price/performance ratio.

 

[bamacre]

Originally posted by: murgaan
Well, that's the thing. I haven't bought a motherboard yet. I'm trying to figure out what motherboard/memory combination has the best price/performance ratio.

Oh, well, ATM, the cost of DDR2 memory is much more expensive than DDR. This was quite different a few weeks ago. But in regards to OC'ing potential, I'm not sure.

 

[murgaan]

I'm not talking about overclocking. I simply want to know how DDR400 dual channel with low latency will perform compared with DDR2-800.

 

[Bobthelost]

It all depends on the socket and how it's used.

Right now only Intel chips use DDR2, although the new AM2 socket from AMD will also support it. Also no chipsets support DDR2 800 speeds as of yet. That will come to both Intel and AMD at around the same time, AM2 being compliant from the start, while the Intel designs being revised for it.

You're doing this in what is possibly the most silly manner ever. What do you want your computer to do first, and then find the chip that does it best in your budget.

 

[murgaan]

I neglected to specify "Intel" in the post; sorry about that.

"Also no chipsets support DDR2 800 speeds as of yet"

What about the 955x and 975x? They seem to support DDR2 800.

 

[Bobthelost]

As far as i know they can't USE the RAM at those speeds.

From Tom's Hardware Guide
Let's also not forget that Intel is going to introduce DDR2-800 support at around the same time as well...

I know it's toms' but i doubt they'd get something that basic wrong.

If you're thinking Intel then why the hell did you refer to DDR? It's not usable in any way with current Intel systems!?

http://developer.intel.com/technology/memory/

Intel makes no mention of DDR2 800 RAM there.

 

[stevty2889]

Originally posted by: bamacre

Originally posted by: murgaan
Well, that's the thing. I haven't bought a motherboard yet. I'm trying to figure out what motherboard/memory combination has the best price/performance ratio.

Oh, well, ATM, the cost of DDR2 memory is much more expensive than DDR.

That doesnt' seem to be the case, DDR2 still looks to be cheaper at the moment(well DDR2 800 is an exception since it's not as common yet), but I just got 2x1gb sticks of CL4 DDR2 667 for $150..

 

[murgaan]

OK, I stand corrected... It seems Bobthelost is correct; there are no chipsets supporting DDR2-800. Well then, that makes the original question that much more interesting.

 

[Bobthelost]

No it doesn't. As there is no way to compare DDR to DDR2 without looking at the CPUs that will run them, which makes a massive difference as the architectures that run the different speeds are so different.

 

[murgaan]

Bobthelost, you write, "there is no way to compare DDR to DDR2"

I don't understand. From Intel's site regarding the 915G chipset:

"Flexible memory support, for dual-channel DDR2 533/DDR2 400 or DDR400/DDR333 memory, in configurations of up to 4 GB RAM."

Could you clarify your statement? It seems trivial to compare the two memories with the same CPU, Intel 660 for example.

Thanks, I'm just trying to wrap my head around this.

 

[bamacre]

Originally posted by: stevty2889

Originally posted by: bamacre

Originally posted by: murgaan
Well, that's the thing. I haven't bought a motherboard yet. I'm trying to figure out what motherboard/memory combination has the best price/performance ratio.

Oh, well, ATM, the cost of DDR2 memory is much more expensive than DDR.

That doesnt' seem to be the case, DDR2 still looks to be cheaper at the moment(well DDR2 800 is an exception since it's not as common yet), but I just got 2x1gb sticks of CL4 DDR2 667 for $150..

Linky for that?

 

[Bobthelost]

It doesn't. The slots are a different physical shape and use different voltages as well as signaling differences. The 915 chipset is DDR i think.

 

[dguy6789]

Aren't current DDR2 solutions also dual channel?

Bandwidth wise, PC2 6400 DDR2(800mhz) is equivalent theoretically to dual channel configured PC3200 DDR. Latency will be lower with the DDR, which matters on the Pentium platform. If you are speaking of an AMD64 platform, they would theoretically be identical because latency means diddly squat on an Athlon 64. PC2 6400 in Dual channel may not help on the current Pentium 4 platform because of the lack of fsb speed. Since the Athlon 64 has no FSB, increasing memory bandwidth available will increase real available bandwidth by that exact margin for quite a while due to the advanced Hyper Transport technology. The problem is, the Athlon 64 does not need much memory bandwidth before it reaches its peak performance, thus even though you allow it access to rediculous amounts of memory bandwidth, it will not increase in performance by that much.

Keep in mind all the information above is theoretical with estimated performance levels based on previous and current memory performance gain scenarios. No hard evidence to back it up.

 

[murgaan]

Bobthelost, I understand that you won't (usually) find DDR and DDR2 on the same motherboard. However, there are motherboards that accept an Intel 630 and have DDR, and there are motherboards that accept an Intel 630 that have DDR2 support. Therefore, it would be easy enough to test.

 

[Bobthelost]

For a minute let's say that's true, why the hell do you care about them? What do you want the RAM to be doing?

 

[ND40oz]

Originally posted by: murgaan
OK, I stand corrected... It seems Bobthelost is correct; there are no chipsets supporting DDR2-800. Well then, that makes the original question that much more interesting.

Gigabyte seems like it supports up to DDR2 888, I don't have any memory that fast, so I can't test it for you.

Here are some boards that support both.

 

[murgaan]

As I originally stated, I want to know if I would be wasting my money on DDR2 memory and motherboard. They seem to be more expensive. I don't mind paying for performance, but if the performance increase isn't noticable... so on and so forth.

To answer your question, with my RAM I'd like to be playing games, recording and playing back video, etc.

Thanks.

 

[Bobthelost]

Then you asked in the wrong manner, what is your budget, if it's over $1k then odds are you'd be best off with AMD of some sort, either way you might want to wait a month for AM2 to see just how much of a performance leap it takes and how the Intel DDR2 hike goes.

 

[murgaan]

The Gigabyte board referenced only supports DDR-667...

Now, what happens to the 800MHz FSB speed when using DDR-667 memory? To my eye that doesn't seem to match as 667 isn't a multiple of 200.

 

[stevty2889]

Originally posted by: murgaan
The Gigabyte board referenced only supports DDR-667...

Now, what happens to the 800MHz FSB speed when using DDR-667 memory? To my eye that doesn't seem to match as 667 isn't a multiple of 200.

Even DDR-533 isn't a multiple of 200, but it doesn't matter, it's running Asynch. DDR2-533 runs at 266mhz, DDR2-667 runs at 333mhz, both run at higher speeds than the FSB.

 

[murgaan]

Now, Bobthelost, I already own the Intel 630. I realize I miswrote above (660); sorry. I'm trying to figure out if I should go with DDR or DDR2.

 

[Bobthelost]

I see, then DDR 400.

 

[stevty2889]

Originally posted by: bamacre

Originally posted by: stevty2889

Originally posted by: bamacre

Originally posted by: murgaan
Well, that's the thing. I haven't bought a motherboard yet. I'm trying to figure out what motherboard/memory combination has the best price/performance ratio.

Oh, well, ATM, the cost of DDR2 memory is much more expensive than DDR.

That doesnt' seem to be the case, DDR2 still looks to be cheaper at the moment(well DDR2 800 is an exception since it's not as common yet), but I just got 2x1gb sticks of CL4 DDR2 667 for $150..

Linky for that?

$151 after $20 mail in rebate