Dual Channel???

[joy_chak]

Hey guys i wannted to know what is a dual channel memory. Is 2 x 256 mb better or just go for one stick of 512 mb ram.

[amitsaudy]

Does your motherboard support dual channel.
Then go for 2 x 256 mb rims to enable the dual channel mode.
It gives a significiant performance boost in the memory subsystem.

[Kniwor]

what is ur motherboard?
if it supports dual channel, get 2x256, it is a big boost

[Ringwraith]

Originally Posted by Kniwor

what is ur motherboard?
if it supports dual channel, get 2x256, it is a big boost

depends on whether you would call a maximum of 10-15 % boost as "big boost", but yes it is preferable to get dual channel memory if your cpu/mobo support it.
if uve got one of those older skt 754 or other single channel soln. that is not a major upgrade issue then, just get more RAM, it will affect performance more than running it in single/double channel.

[Kniwor]

Originally Posted by Ringwraith

depends on whether you would call a maximum of 10-15 % boost as "big boost", but yes it is preferable to get dual channel memory if your cpu/mobo support it.
if uve got one of those older skt 754 or other single channel soln. that is not a major upgrade issue then, just get more RAM, it will affect performance more than running it in single/double channel.

Have u ever run the bechmarks,

the difference is up to 35-40% in some cases, and i have seen it on my comp, and that's a huge difference to say..... just run benchmark friend.

[h_kunte]

Kniwor is absolutely right. The increase in performance is almost 30% to 40%. Dual channel RAM is always recommended as it enables tranferring data at 128kbps than the customary 64 kbps.

Curious: What will happen if I use 3 RAM stix together? Something like 512*3?? Will I b able to call it three-channel memory? Will it incrase the performance? I have heard that one needs upto 4 GB of RAM for intense animation jobs. Does using 4 RAMs together really add o to the performance????

Looking for answers. TiA

HK

[Ringwraith]

Originally Posted by Kniwor

Have u ever run the bechmarks,

the difference is up to 35-40% in some cases, and i have seen it on my comp, and that's a huge difference to say..... just run benchmark friend.

sorry abt breaking your myth, but the real-world performance difference is negligible, while the benchmarks show a ~10 % increase... I would however prefer 1GB of single channel memory over 512 MB dual channel anyday

As for teh original question, Buy dual channel whenever - wherever possible.

Here's a discussion abt dual-channel memory on X-bit, listen to Monk and MTX, they are probably more knowledgeable than any of the folks here.

http://www.xbitlabs.com/forum/viewtopic.php?t=8626

I wud ve posted a better link, if I wasnt starved for time.

[goobimama]

@Ringwraith: He has clearly mentioned that he wants a total of 512MB RAM, either one stick or 2x256. In this case the answer is simple, if the board supports it, go for dual channel. If not, go for 512 to save a slot.

It also depends on what you mean by "Real-world" performance. If playing music and movies is real world, then yes, there is not much increase in performance. But if you keep running filters and work heavy files in photoshop (or many other apps) you will certainly notice the difference.

Question: Me also wants to know whether if I put an additional 512 MB ram in addition to my 1GB dual channel setup, what will be the end result? Will the two remain in dual channel and the extra 512 MB run as single channel? not sure whether to add more RAM cause I can't afford another Gig of RAM

[Nemesis]

Another advantage of a dual channel setup is that if one of your RAM sticks goes bad, you still have the other one to fall back on - in single channel, you're doomed if your single stick goes bad.

@goobimama: I'm not entirely sure but I think that single 512MB stick will mean that even the 1GB you already have will not run in dual channel. Need someone else to clear this up.

[Kniwor]

Originally Posted by Ringwraith

sorry abt breaking your myth, but the real-world performance difference is negligible, while the benchmarks show a ~10 % increase... I would however prefer 1GB of single channel memory over 512 MB dual channel anyday

As for teh original question, Buy dual channel whenever - wherever possible.

Here's a discussion abt dual-channel memory on X-bit, listen to Monk and MTX, they are probably more knowledgeable than any of the folks here.

http://www.xbitlabs.com/forum/viewtopic.php?t=8626

I wud ve posted a better link, if I wasnt starved for time.

just a little test, open everst and see memory read write speeds in single and dual channel, do it urself and post back, and i said upto 35% meaning that is in extreme case, and we are talking about benchmarks here and not real world performance.

[Ringwraith]

@Kniwor
Yeah, memory benchmarking will definitely show the differences. The only thing which I wanted to point out was that, the memory bandwidth is very seldom a limitation in everyday work, unless ofcourse you do stuff which taxes the memory subsystem like video encoding/high res gaming. In most cases, the system is bottlenecked by the disk transfer rate, filesystem or the sheer number crunching power of the processor.

Curious: What will happen if I use 3 RAM stix together? Something like 512*3?? Will I b able to call it three-channel memory? Will it incrase the performance? I have heard that one needs upto 4 GB of RAM for intense animation jobs. Does using 4 RAMs together really add o to the performance????

There is nothing like triple channel memory. Memory controllers as of now support only two channels. One primary requirement for dual channel is that the two RAM sticks should be evenly matched. ie. they should have same memory timings (ideally from the same manufacturer and if possible the same production batch)

@Goobi
I assume you have 2*512 as of now?
If yes, adding another 512 mb stick will disable the dual channel operation for you. Options for you:
1) 2*512 + 1*512 = 1.5 Gb single channel
2) 2*512 + 2*256 = 1.5 Gb dual channel
3) 2*512 + 2*512 = 2 Gb dual channel

since you cant add another gig of RAM, I would ask you to take the first option, and add another 512 mb as soon as you have the money. However it looks like others here might have different opinions

Also what cpu do you have? The newer amd cpus ( >=venice) as well as the P4s can run at a 1T command rate and DDR 400 with all four DIMM sockets populated.
If you got a winch or an older CPU, you might have troubles with 4 mem sticks, you might have to lower command rate to 2T , and revert to DDR 333 as well if you have a clawhammer.

[sagar_coolx]

allright this dual chammel is for ddr 400 modules.
but is there dual channel mode for ddr2?

also,
what are low latency rams?
will a low latency ddr 400 module deliver better performane thn a ddr2 533 or 677 one?

[goobimama]

@Ringwraith:

Thanks a lot for the solution. I think I'll stick in 2*256 RAM....Can always bump if off later..

About this performance thing, I'm not into performing benchmarks and stuff. I had two 1 Gig in single channel mode earlier due to diferent RAM sticks (same timings, different brand) and then I exchanged it for the proper one and got not an astonishing jump in performance, but one I thought was quite worth the effort....

Get it correct lol

The single-channel 64-bit mode will produce roughly 2.7GB/s bandwidth.

where as dual-channel 128-bit will allow upto 5GB/s.

General performance:

There will be almost 40% performance boost in genaral operations.
With dual channel you have two pipelines to the processor from the ram instead of one.




FOR GAMES:

In the real-world gaming there will be very little difference in performance between single and dual-channel modes. approximately aorund 5%.There wont be any increase in frame rates even in the dual channel.


WHat matters for games is the graphics card.
So for games graphics card is the most imporant factor.

And also games are memory capacity independent.That is you will get same frame rate in a game with 512MB or 1024MB or 2056MB.(256MBSuks).
Dont think that you will high fps if u use 2GB memory.


And one more thing
Regarding game loading times,dual channel will be more preferrable.
A game on 512MB dual-channel setup will load much faster than 2GB of single-channel memory.
EX
Battlefield 2 will take 93 seconds to load in 512 MB Dual channel

Battlefield 2 will take 200 seconds to load in 512 MB Single channel

and in all other memory capacities(1GB,2GB) result will be same.i.e. No effect on performance with large capacity.Strange.But in my opinion the the performace of games will be smooth with increase in RAM which cant be measured.

For now,
Get 2x256MB 400Mhz in dual channel.Its enough for a general user.Its better than single channel RAM.If your mobo doesnt support Dual channel get 512MB ram.

1GB dual would be preferrable.

Originally Posted by goobimama

Question: Me also wants to know whether if I put an additional 512 MB ram in addition to my 1GB dual channel setup, what will be the end result? Will the two remain in dual channel and the extra 512 MB run as single channel? not sure whether to add more RAM cause I can't afford another Gig of RAM

The end result will be single channel and reduced performance.

if you decide to add more ram you will need another identical pair of ram to go in the two open slots, if you only add one more, it will see the ram but your back to single channel mode. So it is very important to have the exact same chip in both slots of the same color.

Originally Posted by sagar_coolx

allright this dual chammel is for ddr 400 modules.
but is there dual channel mode for ddr2?

also,
what are low latency rams?
will a low latency ddr 400 module deliver better performane thn a ddr2 533 or 677 one?

yes there is dual channel for ddr2 also.

RAM Latency is the amount of wait time that a computer experiences when trying to access data in its RAM.
RAM latency is measured in front side bus clock cycles.

It’s not just the speed of the memory that matters; latency timings are equally important. A DDR memory running at 400 MHz comes close to beating DDR 2 memory which runs at 533 MHz—simply because the latter has a higher latency. This shows up most clearly when playing Doom 3—the moment the latency timings are lowered, the scores get better lol.
DDR2 566 gives the same performance as DDR400, simply because of latencies. DDR400 can get to about 2-2-2-6 these days, but DDR2 is still like 4-4-4-8 or something.

DDR2 is only faster when it is over 600MHz Frequency.

Transcend 400 MHz RAM is the best buy RAM with good overclocking features and well priced.

[sagar_coolx]

so how much does it cost???

[vijay_7287]

trancend 512mb costs
Rs 2.2k

[jay4u]

one question guys... i recently buyed a transcend ddr 400 mhz ram... now i want to know if it will support the dual channel on my board..... my mobo is 865 gbf intel and its BIOS says it support dual channel.... Does the ram for dual channel mode needs to be different or only the mobo matters.....

and can anyone plz tell me what difference does it make having a single side ram or a double side ram chip..... and which one is better...

[Nemesis]

Only the motherboard matters.

If your board supports it, then just get two identical RAM modules and use them in dual channel.

[jay4u]

thanks buddy... seams like i need to go buy another 512 mn transcend.... i was going to buy it anyways....

And what about the dual sided ram vs. the single sided ram chip.....

[Kniwor]

Originally Posted by Ringwraith

@Kniwor
Yeah, memory benchmarking will definitely show the differences. The only thing which I wanted to point out was that, the memory bandwidth is very seldom a limitation in everyday work, unless ofcourse you do stuff which taxes the memory subsystem like video encoding/high res gaming. In most cases, the system is bottlenecked by the disk transfer rate, filesystem or the sheer number crunching power of the processor.

What if i have integrated graphics that share the memory, itś very important to have high transfer rates, and dual channel is really helpful then.

as u agree that there is a 30-40% increase in memory performance, it is helpful in ways. Now let the third person decide if he wants to get a dual channel or not.

[siriusb]

Originally Posted by jay4u

And what about the dual sided ram vs. the single sided ram chip.....

Dual Inline Memory Modules (DIMM) have 64bit data path whereas a SIMM has only 32bit data path. I don't think there are many simms around with recent processors.

[jay4u]

OKIE... SIRIUSB... DUAL INCLINE MEMORY MEANS HAVING IC CHIPS ON BOTH SIDES OF MMEMORY CHIPS RIGHT.... OR IT HAS SOMETHING TO DO WITH RAM CHIP ARCHITECTURE...

PRETTY CONFUSED... I WANTED TO KNOW THAT IF I HAVE 2 RAM ONE WITH IC ONLY ON ONE SIDE ON IT AND ANOTHER WITH IC ON BOTH SIDES OF IT... THEN WHICH ONE SHOULD I GO FOR....

[siriusb]

Hmm...AFAIK, SIMMs came only for EDO rams, so you can treat that ram module u have as a dimm. As far as DIMM is concerned, two-sides of memory is not important, rather, the data path should be 64 bits. That is, the two sides of the module must have it's own contacts.