Dual Channel with 3 sticks ?!

|Ric| · 15 Jan 2006 at 14:13

I'm still running a socket A system and it has 3 RAM slots, over time I have filled these with 512 sticks.
Obviously I wasn't suprised to see it run in dual channel mode with 2 sticks (provided they are in the right slots) but my motherboard still reports dual channel with 3 sticks. Is it just wrong or does it happen? I guess my only surprise is I would expect that dual channel to involve 2 or 4 sticks

Just curious (and a little confused) really
|Ric|

DanMc07 · 16 Jan 2006 at 05:44

I cant see how your mobo is reporting 3 sticks as dule channle, probably wrong, as dule channle is 2x256,2x512 etc etc??

Dutch Guy · 16 Jan 2006 at 07:21

What dual channel means is that two sticks can be accessed at once, so if you have 3x512Mb the first 1024Mb you use will come from two sticks and will be dual channel, the remaining 512Mb can only come from one stick so will be single channel.

So you have dual channel and single channel

|Ric| · 16 Jan 2006 at 13:23

special

thank you

Ollie's Gadgets · 16 Jan 2006 at 14:38

Thats helped me in fact. Guess I need to sell my 2x256mb and buy 2x512mb, as 2x256mb and 1x512mb will be slower. What kind of performance gain does dual channel give over having 3 installed memory chips? Is it significant?

Dutch Guy · 16 Jan 2006 at 14:55

Ollie's Gadgets said:
Thats helped me in fact. Guess I need to sell my 2x256mb and buy 2x512mb, as 2x256mb and 1x512mb will be slower. What kind of performance gain does dual channel give over having 3 installed memory chips? Is it significant?

If you have three memoryslots you can put 2x256mb in one channel and 1x512mb and have 1gb dual channel memory.

you need to put the 256mb sticks in the two slots close together and the 512mb in the slot on it's own.

Ollie's Gadgets · 16 Jan 2006 at 16:02

Are you sure this will work with an older motherboard. I have the abit nf7-s which I didn't think could do that...

Dutch Guy · 16 Jan 2006 at 18:53

Ollie's Gadgets said:
Are you sure this will work with an older motherboard. I have the abit nf7-s which I didn't think could do that...

Yes, I'm sure, I had that mobo as well so did some research.

Ollie's Gadgets · 16 Jan 2006 at 21:09

Many thanks Dutch Guy.

Vegeta · 16 Jan 2006 at 21:13

Hmm ive got this motherboard - i cannot get 2X256mb and 1X512mb sticks to work in it all together.
The two 2X256mb are dual channel and the 1X512mb is a single.
It does work but the pc is prone to crashes when playing intensive pc games - i made a thread about this before and they said it was due to ram.

Ollie's Gadgets · 16 Jan 2006 at 23:50

What ram are you using Vegeta?

Bookime Wood · 17 Jan 2006 at 00:14

Ran asus with 3 sticks, post reports dual channel

Ran nf7-s slot 1 = 1x512 slot 2+3 = 2x256 dual channel

cpuz also reported dual channel, but have read that although it may report running dc at post in windows it might not be?

Vegeta · 17 Jan 2006 at 01:09

Im running Geil Ultra cas2 (not ultra x)

Dutch Guy · 17 Jan 2006 at 08:32

There are three memory slots:
|| |
The left two are connected to one channel and the right one as well.
If there are two 256mb sticks in the left two slots and one 512mb stick in the right slot it means there is 512mb memory connected to each memory channel.

If your system needs memory it will be shared between memory channels.

The problem with running three sticks of memory is that the more sticks you have the more stress it is for the mobo and you will be limited by the slowest/worst stick.
What you can do is raise the memory voltage and see if that helps, if not slacken the timings starting with CAS.

james.miller · 17 Jan 2006 at 08:46

it's so hard to convince people of something that should be so easy to understand.

Basically, dutch guy is spot on. The 'channel's are hardware on the board. They are the memory controllers that read and write to the ram and they are running at all times. You can not switch them off. Therefor if they have memory in one of their assigned slots, they will use it. If they both have memory, regardless of wether one has more than the other, you got yourself dual channel there kid.

Dutch guy was also right about the remaining ram when running 3 sticks - it will be accessed as if it's single channel.

Vegeta · 17 Jan 2006 at 13:00

Dutch Guy said:
What you can do is raise the memory voltage and see if that helps, if not slacken the timings starting with CAS.

Hi i have 2X256 and 1X512 running, on memtest86 they kept failing test #5 however individually they were all stable, I then realised when I use all three sticks my problems occur.
I've now upped the voltage from 2.6 to 2.7, memtest no longer gets the error - is that the problem fixed now?
I will be leaving it overnight just to make sure.

Dutch Guy · 17 Jan 2006 at 13:05

Vegeta said:
Hi i have 2X256 and 1X512 running, on memtest86 they kept failing test #5 however individually they were all stable, I then realised when I use all three sticks my problems occur.
I've now upped the voltage from 2.6 to 2.7, memtest no longer gets the error - is that the problem fixed now?
I will be leaving it overnight just to make sure.

When I had a NF7-S I had to run my memory at 2.9V (I had cheap TwinMOS memory)

But I remember a lot of people having problems with Dual Channel stability.

Vegeta · 17 Jan 2006 at 13:23

Glad its not just me then - I'll run it over night and see if its stable.