Memory question regarding dual channel.

just Scott · 10 Dec 2006 at 20:16

Right now i have 2*512mb modules of Corsair Value Select PC3200.

I really need to upgrade to 2GB as the programs I use and the ammount of things running at once are really slow right now.

I would sell these two modules and get 2*1GB modules for better performance, but I have no idea how I would sell them (I don't want to use eBay). So, I was thinking of adding another 1GB module of RAm to make 2GB. If I did do this it would looks like:

slot 1: 512MB
slot 2: 1GB
slot 3: 512MB
slot 4: empty

Would slot 1 and 3 still be in dual channel with this setup? Or would it be lost due to the 1GB in the middle?

Just wondering if I should wait till I find out how I would sell these and get a proper kit of 2GB, or just go with the above setup.

Thanks.

postmanfw · 10 Dec 2006 at 21:01

If u put the 512 in slot one and two and 1gb in slot three you might still get dula channel with the whole lot. Bit of luck as well plus make sure you get the exact same type of ram. Works for some socket A's but not sure about other boards

just Scott · 10 Dec 2006 at 21:40

postmanfw said:
If u put the 512 in slot one and two and 1gb in slot three you might still get dula channel with the whole lot. Bit of luck as well plus make sure you get the exact same type of ram. Works for some socket A's but not sure about other boards

Well the only 1GB stick OCUK stock isn't the type of RAM I have.

However, they do stock the same kit I have (2*512MB Corsair), with the same model and everything. So I could ahve 4*512MB or 2*512MB + 1GB.

Which would be better? 3 sticks, with 2 different models. Or 4 sticks of all the exact same model?

Thanks for the reply btw.

Dureth · 10 Dec 2006 at 22:35

What CPU and mtoherboard are you using? If its an athlon 64 then you cant use 3 sticks of RAM full stop, it doesnt work. Best bet would be to either sell and get 2x1GB or at a push get 4x512MB. If your on any other CPU you will definately lose dual channel by putting in a 3rd stick.

just Scott · 10 Dec 2006 at 23:23

Dureth said:
What CPU and mtoherboard are you using? If its an athlon 64 then you cant use 3 sticks of RAM full stop, it doesnt work. Best bet would be to either sell and get 2x1GB or at a push get 4x512MB. If your on any other CPU you will definately lose dual channel by putting in a 3rd stick.

I'm using a AMD x2 3800+ with an ASUS A8N-E motherboard.

I don't care about overclocking. I just want better stock performance. And by the sound of it, it's best to go with 4*512MB sticks.

I want to sell the other modules but I have no idea how I would go about it other than eBay. But I don't know how to use eBay, lol.

WJA96 · 11 Dec 2006 at 10:36

The best stock performance will come with 2 1Gb sticks of RAM. There are loads of ways to sell your existing RAM - local paper etc. but the best way if you're not that fussed about ebay is to use the OCUk Member's Market. You currently need 250 posts and be a member over 90 days to access it, but if you have been a member a long time you may be able to get in with 100 posts I think.

Edit - just checked and you need about another 90 posts to get access. Don't go silly, but if you are at home all day it shouldn't take long to run up one hundred posts

Bolerus · 11 Dec 2006 at 14:38

i may be barking up the wrong tree, i often do

but if your motherboard has 3 slots, then I woudl be very very surprised if it is dual chanel, I woudl recomend checking that in your manual or on the web.

Dual chanel memmory will not be dual chanel if it isnt in a dual chanel motherboard. In fact it may even not work at all in a non dual chanel MB (i may be wrong there as well, with the memmory being alegedly backwards compatible)

and even if your motherboard is dual chanel with the 3 slots, you need to have the same size memmory in the dual slots for it to work

no of course i fully accept that I have not kept up with technological advances over the last 2 years or so, so things may have changed and I coudl be talking out of my somewhat outof date bottom.

doesent hurt to do the research before you buy though

james.miller · 11 Dec 2006 at 14:43

dual channel = 2 memory controllers working in parallel. as long as you give both controllers acces to memory, it'll be dual channel. whether it'll work or not comes down to the chipset's memory support. Ie, will it work with 3 sticks of ram?

as long as they can run at the same timings, there's no reason why 2x512mb on one channel and 1x1gb on the other wouldnt work other than if the chipset and cpu itself doesnt support it. for example, i and many others had no problems running dual channel with 1x512mb and 2x256mb sticks on our old socket-a amd system, despite many many people telling us otherwise. The reality is most people dont understand what 'dual-channel' actually is.

just Scott · 11 Dec 2006 at 15:29

WJA96 said:
The best stock performance will come with 2 1Gb sticks of RAM. There are loads of ways to sell your existing RAM - local paper etc. but the best way if you're not that fussed about ebay is to use the OCUk Member's Market. You currently need 250 posts and be a member over 90 days to access it, but if you have been a member a long time you may be able to get in with 100 posts I think.

Edit - just checked and you need about another 90 posts to get access. Don't go silly, but if you are at home all day it shouldn't take long to run up one hundred posts

Ah, I never thought about the Members Market, I guess I'll wait until I get access to it to sell these though. I guess I can wait a while.

Bolerus · 11 Dec 2006 at 16:32

james.miller said:
dual channel = 2 memory controllers working in parallel. as long as you give both controllers acces to memory, it'll be dual channel. whether it'll work or not comes down to the chipset's memory support. Ie, will it work with 3 sticks of ram?

as long as they can run at the same timings, there's no reason why 2x512mb on one channel and 1x1gb on the other wouldnt work other than if the chipset and cpu itself doesnt support it. for example, i and many others had no problems running dual channel with 1x512mb and 2x256mb sticks on our old socket-a amd system, despite many many people telling us otherwise. The reality is most people dont understand what 'dual-channel' actually is.

Whilst I understand your logic. I disagree, If the mother board in question is not dual chanel, then no matter what you do, you will not be able to run memmory dual chanel, it is simply down to mother board support.

And as I said in my post, I woudl be surprised, but not shocked, if you knwo what i mean, to find a motherboard with 3 slots that has dual chanel

Bolerus · 11 Dec 2006 at 16:33

And yeah you can tweek timings to get them optimal, but without dual chanel support on a Mb they arnt going top be dual chanel

james.miller · 11 Dec 2006 at 16:34

Bolerus said:
Whilst I understand your logic. I disagree, If the mother board in question is not dual chanel, then no matter what you do, you will not be able to run memmory dual chanel, it is simply down to mother board support.

dual channel = 2 memory controllers working in parallel. as long as you give both controllers acces to memory, it'll be dual channel.

obviously, your motherboard has to have two memory controllers. Its not my logic, its the way it works.

Bolerus said:
And as I said in my post, I woudl be surprised, but not shocked, if you knwo what i mean, to find a motherboard with 3 slots that has dual chanel

abit nf7-s, the board i commented on in my previous post and, for that matter, so did 99% of the rest of the nf2 boards.
http://images.google.co.uk/images?q...a:en-GB:official&client=firefox-a&sa=N&tab=wi

Bolerus · 11 Dec 2006 at 16:49

it says there in balck and white it is dual channel

and features new dual 400MHz DDR memory controllers that deliver up to a 50% increase in bandwidth

So what is your argument there? of course a motherboard with dual support will run dual.

But I am surprised to see a dual chanel mother board with 3 slots, seems like a bit of a cop out to me, if you look on the pic of the MB you can clearly see that slots 1 and 2 are together and then a gap till slot 3. why bother doing that, surely putting an extra mem slot so you have 2x dual chanels wouldnt cost much extra but anyway, that is their choice.

If you were posting that to show me that there are 3 slot mbs with dual chanel support, then thanks, I hadnt seen one previously.

But I stand by the statement, if a mother board does not support dual chanel (And that one, liek most modern MBs does) then you cant run memmory as dual chanel.

I am begining to think we are disagreaing about the wrong thing if you know what i mean.

james.miller · 11 Dec 2006 at 16:53

Bolerus said:
But I stand by the statement, if a mother board does not support dual chanel (And that one, liek most modern MBs does) then you cant run memmory as dual chanel.

I am begining to think we are disagreaing about the wrong thing if you know what i mean.

im not disagreeing with anything! i said if it has two controller and both controllers have access to ram it'll run in dual channel provided the chipset supports the memory configurations.

me said:
dual channel = 2 memory controllers working in parallel. as long as you give both controllers acces to memory, it'll be dual channel. whether it'll work or not comes down to the chipset's memory support. Ie, will it work with 3 sticks of ram?

its right there ^^. i never said anything about motherboard with only one controller, such as the socket 754 AMD motherboard.

just Scott · 11 Dec 2006 at 17:30

Just so you guys know, my motherboard has 4 DIMM slots, lol.

>_<

Bolerus · 12 Dec 2006 at 09:00

In that case, have you thought about seeing if anybody wants to swap your 1gig stick for 2x 512s

that way (As long as you get the same speed) you will have your 2gig, you will have all 4 slots used, and you will using the memory dual chanel for optomised performance

It would suit somebody that wants to do the same thing but with 1gig sticks