how to tell if Memory is Dual?

[UARMF]

Hey All, How do i tell is my Memory is Dual Channel or not? it's pc2700 1GB but the Bios only sees 512MB. The Bios Does Support Dual Channel (Double sided)

[Das Capitolin]

Unfortunatly double-sided does not mean dual-channel. Dual Channel is primarily an Intel feature that means two memory modules placed in DIMM sockets 1 and 3 will become one dual-channel set, and if you have more RAM it would go into sockets 2 and 4.

[Gray]

The ram is not actually "dual chanel RAM". sometimes you will see dual channel RAM kits for sale out there. This is to make sure that the 2 sticks are exactally the same wich they need to be, when you want to use them in a dual channel set up.

The motherboard is what decides weather or not to us the 2 sticks (or 4) in dual channel mode or not.

Das was correct in saying that slot placement is key when you want your motherboard to use the RAM in dual channel mode. You will need to consult your motherboard manual to see what capacity, what positions, and weather you can do it with single or double sided chips.

If you add more ram and use say 4 peices you may also find they all have to be the same capacity, or all 4 may need to be identical.

I hope this helps.



I stole this little snippet from someones webpage...

Right now both AMD and Intel have dual channel memory chipsets available (for AMD it is NForce2, for Intel it is i875 and i865). You get about 15%-25% increase in performance by using a dual channel memory system. It is easy to see why - a single channel of PC3200 memory has a bandwidth of 3.2GB/sec. If you use a dual channel memory system, and two sticks of PC3200, you get 6.4GB/sec of bandwidth.

[werty316]

Hey All, How do i tell is my Memory is Dual Channel or not? it's pc2700 1GB but the Bios only sees 512MB. The Bios Does Support Dual Channel (Double sided)
This doesn't really make sense but dual channel means "matched pair" memory sticks that have the same serial number hence the name "matched pair".

Dual channel memory effectively doubles data throughput from RAM to the memory controller. Dual Channel-enabled memory controllers utilize two 64-bit data channels, resulting in a total bandwidth of 128 bits, to move data from RAM to the CPU.

To think of how dual channel works think of it as a road, one with a single lane and another with two lanes; vehicles are data being transfered. A two lane road allows more vehicles through as apposed to a single lane road.

[Gray]

I thought I clarified that.
hmmm.

I guess I should add, if your ram is a new "Set" and you bought 1 Gig and are only showing 512MB then maby in those slots you motherboard only accpets single sided RAM sticks.

[Assassin]

CPUz is a wonderful program, open it up and go to the memory tab and it'll tell you if its running in dual channel. Also gotta make sure the ram says dual channel capable along with your motherboard and having the ram in the right slots to enable it. :)

[DragonMaster]

Unfortunatly double-sided does not mean dual-channel. Dual Channel is primarily an Intel feature that means two memory modules placed in DIMM sockets 1 and 3 will become one dual-channel set, and if you have more RAM it would go into sockets 2 and 4.

It isn't always slot 1&3 tho. Both of my 939 mobos run in dual when using 1&2 and 3&4. You have to look in the manual to know which slots are channel A & B(One stick in A, one stick in B) The color of the slots doesn't mean anything also. Sometimes it can be matched to the same channel, sometimes it means which slots you need to use for dual channel

You have to look in your motherboard's manual to see if it supports 1GB sticks. If it does, you have to look if it can work with single-sided 1GB sticks or if it needs double-sided ones. Also, you have to look if the stick has 4 or 8 chip per side, or it might use only half of the RAM. (Some mobos will only show up half the RAM with 4 chip per side RAM)

[Gray]

gotta make sure the ram says dual channel capable

It is good if it does but none of mine does. It's just marketing that says it's better. If it works it works if they are not the same you will know about it as soon as you try to game usually.

Buying dual channel kits are always a lot more expensive.

The 2 "sticks" just have to be the same.

[DragonMaster]

gotta make sure the ram says dual channel capable

Aren't just two same sticks working?

[GIBSON]

Aren't just two same sticks working?
Not always. There might be some stability problems. That's why the manufacturer tests each and every stick on a dual channel motherboard. When two sticks have been tested in one of those mobo's and they are a stabile couple, they go into a dual channel pack. This doesn't mean that if you buy two of the same, but separate sticks it won't work, however you have no assurance that they will work in dual channel config.

[werty316]

Aren't just two same sticks working?
You can use two different sticks and they might work in dual channle but primarly dual channel kits are in "matched" pairs to minimize any conflicts as appose to using two different sticks even if they look the same and have the same specs.

[DragonMaster]

Well, matched is always better, but say you already got one stick and buy an other same model / same chips you've got a lot of chances that they will work together.

[werty316]

Well, matched is always better, but say you already got one stick and buy an other same model / same chips you've got a lot of chances that they will work together.
More chances in this case they would work than if they weren't the same model.

[DragonMaster]

More chances in this case they would work than if they weren't the same model.

I guess I've been lucky with my Athlon XP 2000 then. Two different mfgs, same Samsung chips, rock solid system - DDR266 runs at CAS2 1T IIRC.

[Kougar]

I could be wrong as I haven't checked this, but I always assumed you could take any two sticks of RAM, match the size, timings, and voltages to a T and it'd work. But yer right, doing so probably guarantees that you end up with the same manufacturer chips... :lol: