About Dual Channel Memory

[bimbla]

I want to have dual channel memory.
I have shortlisted Kingston HyperX, 2 X 256, PC 2700.

Will 2 DIMM's do the job or is there anything else called 'matched pair' or 'Dual channel enabled' RAM?

Thanks and regards.

bimbla.

[Boba_Fett]

I want to have dual channel memory.
I have shortlisted Kingston HyperX, 2 X 256, PC 2700.

Will 2 DIMM's do the job or is there anything else called 'matched pair' or 'Dual channel enabled' RAM?

Thanks and regards.

bimbla.

As long as they are the same make and brand you will be fine. "Matched Pair" sets are nothing but a companies way of charging you $10 more for 2 regular sticks of ram.

[Bhairav]

I want to have dual channel memory.
I have shortlisted Kingston HyperX, 2 X 256, PC 2700.

Will 2 DIMM's do the job or is there anything else called 'matched pair' or 'Dual channel enabled' RAM?

Thanks and regards.

bimbla.

As long as they are the same make and brand you will be fine. "Matched Pair" sets are nothing but a companies way of charging you $10 more for 2 regular sticks of ram.

I've run 2 sticks of 256MB RAM, different make, in dual-channel. Works well..

[Shredder]

Any pair of memory sticks that can interleave, can be used in dual channel.

[hoxlund]

I want to have dual channel memory.
I have shortlisted Kingston HyperX, 2 X 256, PC 2700.

Will 2 DIMM's do the job or is there anything else called 'matched pair' or 'Dual channel enabled' RAM?

Bimbla.

well just because you have 2 matching sticks doesn't mean you can run dual channel, remember you still must have a dual channel mobo

but running dual channel is sweet, wouldn't go back, and in a few months its gonna be even better running ddr2 dual channel

[Shredder]

in a few months its gonna be even better running ddr2 dual channel

Well, they've been available for a few months. You can buy DDR2 memory sticks online and run them in dual channel in the latest Intel 9x5 chipset based motherboard.

[hoxlund]

no i know that, just saying when i get the intel bundle with a 915/925 chipset ill be switching all my stuff over

[bimbla]

I have three slots in my mobo. One green and two purple.
If I populate one green and one purple with 266MB each and the other with 512MB, what is the total config. work out to?
2 X 256 Dual DDR + 512 DDR or
1GB Dual DDR or what?

bimbla.

[hoxlund]

in order to get dual channel you can only use the 2 256mb sticks

usually you have to put them in same color memory slots

if you want non-dual channel and use all 3 sticks you'll have 1GB

[CowboySlim]

Hox is right, referring to memory as "dual channel" is a total misnomer. The dual channel functionality is in the motherboard. Two matching sticks in a mobo that does not have dual channel capablity will just be operating as single channel. Two mismatched sticks in a dual channel capable mobo will operate as single channel. A dual channel capable mobo requires a matched set of memory sticks.

Slim

[hoxlund]

well they don't have to be same exact sticks but i think it has to be same size and general cas timings and speed

[CowboySlim]

Hox is right again: size, latency and speed. But getting a matched set guarantees those.

Slim

[tazdevl]

The only reason to get a dual channel kit is if you plan to overclock. Depending on the manufacturer and RAM chips used, you might find one DIMM holding you back from a significantly higher overclock.

As others have mentioned, just be sure you have the same speed and timings.

With respect to size, the general rule of thumb is that as long as you have the same amount of RAM in each bank, you don't have to have the same number of DIMMs. Granted this does vary by manufactuer. Some companies have much greater compatibility with your RAM manufacturer/configuration than others. Typically those companies are Tier1 and the high end of Tier2.

My FSB is running @ 274 MHZ 1:1 (DDR 548), so IMO, a dual channel kit was a wise investment.

[Shredder]

The only reason to get a dual channel kit is if you plan to overclock. Depending on the manufacturer and RAM chips used, you might find one DIMM holding you back from a significantly higher overclock.

Dual channel has nothing to do with overclocking. Running memory in dual channel is to increase performance by eliminating memory bandwidth bottleneck.

[pranav81]

The only reason to get a dual channel kit is if you plan to overclock. Depending on the manufacturer and RAM chips used, you might find one DIMM holding you back from a significantly higher overclock.

Dual channel has nothing to do with overclocking. Running memory in dual channel is to increase performance by eliminating memory bandwidth bottleneck.

Shredder is right.


::Pranav::

[cfitz]

The only reason to get a dual channel kit is if you plan to overclock. Depending on the manufacturer and RAM chips used, you might find one DIMM holding you back from a significantly higher overclock.

Dual channel has nothing to do with overclocking. Running memory in dual channel is to increase performance by eliminating memory bandwidth bottleneck.

Shredder is right.

I think you two have misinterpreted what Tazdevl was saying (either that or I have misinterpreted what you two are saying ). I don't think Tazdevl was saying that dual channel memory is only for overclocking. Instead, he was saying that, in his opinion, the dual channel specially matched kits are only really useful if you plan to overclock your dual channel setup. In other words, you can use dual channel memory without overclocking and, in that case, don't necessarily need the specially matched kits and can just use any two sticks with the same specifications. However, if you do plan to overclock that would be one situation where you might want to consider the specially matched kits. The specially matched pairs are more likely to match each others capabilities with respect to overclocking so you don't end up limiting your overclock because one stick gives up at a much lower overclock than the other.

Anway, that is how I interpreted Tazdevl's comments.

cfitz

[tazdevl]

As fitz said, Shredder & pranav, you missed my point. I'm very much aware of the purpose of a dual channel board, especially given the fact that I have one.

The original poster asked if they should buy 2 DIMMs or a dual channel kit. Boba stated a dual channel/matched pair kit was just a reason to charge more per stick, i.e. don't bother.

I wholeheartedly disagree, if you plan on overclocking the board. The additional cost for bench-testing the 2 DIMMs and the premium is justified based on my experience.

So I'll say it again... if you plan on overclocking a dual channel board, buying a dual channel/matched pair kit is a good idea because the probability of one DIMM holding you back is fairly high if you go with 2 unmatched DIMMs.

If you aren't going to overclock, as others have said... you can use different, unmatched DIMMs as long as the CAS timings and speed are the same. Size doesn't generally matter as long as the total amount in both channels matches. However, this does of course does depend on the manufacturer of the board as some are more compatible with different memory and configurations than others.

[Shredder]

So I'll say it again... if you plan on overclocking a dual channel board, buying a dual channel/matched pair kit is a good idea because the probability of one DIMM holding you back is fairly high if you go with 2 unmatched DIMMs.

Now I see what you meant to say.

[bimbla]

Is there any performance diff. betn. Valueram and hyperX at their RATED speeds?
What if you put PC3200 in Mobo that supports PC2700 max? The sys. wont start or will it start with PC2700 performance?

bimbla.

[Shredder]

Is there any performance diff. betn. Valueram and hyperX at their RATED speeds?

HyperX series memory sticks can run stably in overclocked systems than ValueRAM series can. HyperX are mostly CL2 and few 2.5's while ValueRAM are mostly slower CL3 and few CL2.5's. Check this site for a simple explanation of CAS latency. http://www.corsairmemory.com/main/trg-cas.html

What if you put PC3200 in Mobo that supports PC2700 max? The sys. wont start or will it start with PC2700 performance?

It will run it at PC2700 or whatever memory FSB speed the system is running at.

[pranav81]

Well.....I just thought that tazdevl was saying that DC memory is only for overclocking.I misinterprated the "only" in the following sentence ,"The only reason to get a dual channel kit is if you plan to overclock."


::Pranav::

[CowboySlim]

What if you put PC3200 in Mobo that supports PC2700 max? The sys. wont start or will it start with PC2700 performance?

That depends on the board. Some boards accept memory rated faster than the board will run at, but the board "supports" the faster memory in that it will still run, albeit at the board speed. Therefore, the faster memory has no functional advantage.

OTH, my board has a max rating of 333MHz, equivalent to PC2700, and will not run at all with PC3200 memory installed.

Check your board specs.

Furthermore, if your board supports PC3200 (400MHz) and will run at 400MHz, replacing installed PC2700 with PC3200 will, in most applications, result in very minor performance increases.

Slim

[Shredder]

OTH, my board has a max rating of 333MHz, equivalent to PC2700, and will not run at all with PC3200 memory installed.

PC3200 is compatible and can run as PC2700. Your motherboard probably needs BIOS upgrade as that problem maybe a bug in BIOS.

[CowboySlim]

OTH, my board has a max rating of 333MHz, equivalent to PC2700, and will not run at all with PC3200 memory installed.

PC3200 is compatible and can run as PC2700. Your motherboard probably needs BIOS upgrade as that problem maybe a bug in BIOS.

Not exactly, it is an inherent characteristic of the motherboard, Intel D845GEBV2. However, I haven't updated the BIOS in a while and there now may be one that accomodates PC3200.

Slim

[Shredder]

Not exactly, it is an inherent characteristic of the motherboard, Intel D845GEBV2. However, I haven't updated the BIOS in a while and there now may be one that accomodates PC3200.

According to JEDEC DDR SDRAM specification, they are compatible. It is either Intel chipset or BIOS bug.