Trying to run memory on Dual Channel

[Ricko97]

Bleh.

I received my new parts today, including a stick of Crucial 512mb 184-pin DDR PC3200 RAM. I already have one of those, and previously I was running it with two slower sticks of RAM (on single channel, @333mhz). So obviously I was planning on running both Crucial sticks on Dual Channel mode. Unfortunately my system is being stubborn and is running them on single channel anyway.

I have an A8N-SLi SE motherboard, and after consulting the manual (!) I noticed I didn't stick the sticks (heh) in the right slots... although it isn't written very well, so I'm still a bit unclear on where to install the modules. The slots go something like this:



Channel A:
===================== A1
===================== A2

Channel B:
===================== B1
===================== B2




So, I put them in slots A2 and B2. Then I went into the bios. The speed had increased from 333mhz to 400! Huzzah! But, unfortunately, it starts up and says it's in Single Channel mode. I have tried running just one stick first, then rebooted with the second stick installed, as I know some mobos have issues detecting RAM. No luck. I think I may be using the wrong slots, but I'm not sure. The manual says these two things, which throw me somewhat:

\"For dual-channel configuration, the total size of the memory module(s) installed per channel must be the same for better performance (DIMM_A1+DIMM_A2=DIMM_B1+DIMM_B2)\"

\"When using two DDR DIMM modules, install into DUMM_A1 and DIMM_B1 slots only\"


I -think- I have installed them in the right slots but am not sure. Can anyone suggest why it refuses to run on dual channel? My brother said I may need to update my bios, but I'd rather leave that option until last.

Thanks in advance

[Biodoid]

as far as I understand if you use slots A1 and B1 or A2 and B2 it should run dual channel (so same color slots)

as long as the ram is same speed and same timings then it should run dual channel.. I have 2 1gig sticks of crucial in the same color slots and 2 1gig hynix sticks in the other color slots (different mobo though) and it runs dual channel although with a 1T command rate..

[Ricko97]

I will try them in A1 and B1.

Oh, and something I should point out - as far as I know, both sticks of RAM are -exactly- the same (see it here: http://www.aria.co.uk/Products/Components/Memory/DDR/DDR400+%28PC3200%29/+Crucial+512MB+184-PIN+DIMM+DDR+3200?productId=24229). They even have the sane part code (CT6464Z40B). However, one of them has chips on only one side, whilst the other has chips on both sides. Odd....

Anyway I will try moving the modules now, I'll update with the results.

[mac124]

[quote:8ac885c352=\"Ricko97\"] However, one of them has chips on only one side, whilst the other has chips on both sides. Odd...[/quote:8ac885c352]

I suspect this is probably the problem and you may find there is no way around it, i could be wrong though.

[Ricko97]

Crap.

Now that is annoying, because with my last upgrade, I ordered the first stick from Aria, and it is double rank... and I ordered a second of the same stick, from Aria (again), and it's single rank for some reason.

Perhaps I could return one of them and get a double rank version of the module to match my current? :cry:

If not, then I will have to stick with this. On the bright side, I am no longer running modules made by different manufacturers, and the speed is now 400mhz rather than 333.

Thanks for the help anyway.

[Cheule]

This is why companies like Aria et al sell sticks of mem in pairs, they've been tested in pairs at the factory and are guaranteed to run in dual-channel mode. Unfortunately in your case you appear to have two chips, while identical in make and size, are not identical in construction. This could be the key problem unfortunately :(