Not Dual-channel compatible DDR?

[isochar]

Could someone explain why certain types of DDR won't work in a dual-channel mobo? (ie. Kingston value RAM)

[Gurm]

*shrug*

I have an unclear understanding of Dual-Channel.

Some dual-channel RAM won't work in a non-dual-channel board, either!

- Gurm

[KvHagedorn]

Check with the board manufacturer. Usually the better manufacturers will give you a list of RAM types they approve for their boards. Some dual-channel setups require registered memory.

[isochar]

KV, this isn't even in regards to a mobo. I have a box with a single stick of Kingston ValueRAM (KVR333/256R) sitting in front of me. On the front of it there is a disclaimer saying "Not Dual-Channel Compatible".

I was curious why this is, and secondly, whether manufacturers are claiming "not compatible" when it's really just the same module that hasn't been verified to run for dual-channel setups. (ie. Athlon XP vs MP in the earlier days)

*edit* Just a thought, does a module have to be dual-sided to run in a dual-channel setup? From the tech specs for the ValueRAM, it seems it is indeed single-sided:

http://www.valueram.com/datasheets/kvr333_256r.pdf

[lAmerZ]

kinda marketing Hype

[Jorden]

Re: Not Dual-channel compatible DDR?

(ie. Kingston value RAM)

The "value" gave it away. It's a semi tested version of the Kingston RAM.

Just go for the really (expensive) PC3200 (DDR400) sticks to get tested dual channel DDR. TwinMos is a good choice, or so I am told.

[Admiral]

There's no guarantee that those dual channel certified kits would work also.
I had the "distinct pleasure" of testing two of those expensive Corasir TwinX XMS3200LL kits last June that didn't want to work at 400Mhz no matter what.
If you want to be relatively sure that your ram will work in dual channel mode at 400 MHz you'll have to buy PC3500 or above ram.

Heck, there are enough problems matching ram sticks and finding the right timings for them on single channel systems, dual channel on i865/i875 is just memory upgrade hell.

[Jorden]

Then again, a SuperMicro X5DAE calling itself a High-end workstation, server, and internet application is going a bit too far, in my very humble opinion.

What's wrong with the A-brands?

Another thing about that mobo, if that's the one we're talking about... it's max FSB is 533MHz, so you can't even run at 800MHz Dual Memory speed.

Unless it has had a BIOS upgrade that isn't shown on the site.

[isochar]

They're expensive. I'm building a cheap server where dropping $150 on RAM is the equivalent total of what I spent on the case, mobo, processor, and hard drive. (This RAM is not intended for my X5DAE, but a Gigabyte GA-7N400-L )

[KvHagedorn]

Originally posted by Jorden
Then again, a SuperMicro X5DAE calling itself a High-end workstation, server, and internet application is going a bit too far, in my very humble opinion.

What's wrong with the A-brands?

Another thing about that mobo, if that's the one we're talking about... it's max FSB is 533MHz, so you can't even run at 800MHz Dual Memory speed.

Unless it has had a BIOS upgrade that isn't shown on the site.

LOL I always thought Supermicro was one of the A-brands, unless something drastic has changed about them over the past 2 years or so. Damned stable and built like a tank.

btw, welcome back Jord

[Jorden]

Originally posted by isochar
Gigabyte GA-7N400-L

GA-7N400-L is the excellent platform for latest AMD Athlon XP 400MHz FSB processor.

(source: GA-7N400-L site.)

I hope I don't have to spell it out?
Okay, okay, I'll spell it out then...

Maybe that the 64bit AMD can do dual channel memory, but the XP/MP CPU can not.

Try a real processor for this.
(Just kidding, not trying to be abusive. But as far as I know, the XP/MP CPUs and their mobos still can't do dual channel memory operations. Sorry.)

[Jorden]

10 edits later... oh that's what the preview button is for?

Errm so what's that quick answer window for? (No, not trying to hi-jack this thread )

[Greebe]

TwinMos is a good choice, or so I am told.

Jord, what does your imply?

[isochar]

Originally posted by Jorden

Try a real processor for this.
(Just kidding, not trying to be abusive. But as far as I know, the XP/MP CPUs and their mobos still can't do dual channel memory operations. Sorry.)

I seem to have some difficulty knowing when you're joking and when you're being serious!

On the same page you linked:

Dual Channel DDR400 memory architecture support
With the Dual Channel DDR400 memory architecture, this platform delivers high capacity of 3GB memory and high bandwidth up to 6.4GB/s to ensure greatest memory performance.

And here:

http://anandtech.com/chipsets/showdoc.html?i=1731&p=2

The nForce & nForce2 both come in dual-channel varieties.

[Jorden]

What? You never seen an emoticon before? The wink emoticon just means that I have read/been told through some mags & sites that that memory is apparently the best.

A frind of mine is using it in his rig and he doesn't want to part with it. Can't speak for myself, as I can't use it.

Does that mean I can't give a pointer in that direction then?