3 memory slots in my asus A7N8X - how I use them?

[zakimort]

I apologise for the stupid title, with few characters i couldnt say a lot.

I have an ASUS A7N8X deluxe, which has 3 slots for memory.
At the moment I have 2x512MB installed, but want to but [today, lol] a 1024GB stick.
I was reading some posts in here, and I may have understood that i will have to put the 2 512MB stick in slots 1 and 2, and the 1024MB in slot 3.
This is the first time I add a memory expansion on my own, when I had it upgraded from 512 to 1024 a friend of mine was helping me and anyway there was so sequence problem. I am so excited :D
Please can you tell me what is the better way to place them?
the 2 little together and the bigger alone? or?
Or maybe it should be better if i buy another 512 instead of the 1024? I hope not.
Thank you in advance for any answer you can give me
--EDIT-- in the manual i read that the way they are positioned can enhance system perfomance [or probably slow it down, who knows, if i do it wrong]

[zakimort]

sorry I had to repost because i wasn't allowed to edit the previous post again. I don't think I explained at all what my problem is, so now I try to be a bit more clear.
the picture of the board [which can be seen at
http://www.linuxhardware.org/images/articles/nf2kt400-071003/ASUS-A7N8X-Board.jpg
shows dimm1 as the black one, dimm2 as the blue very close to 1, and dimm3 furter on the right. What I would like to know is where to put the 1024MB stick and where the 2 512MB ones. The fact that one of the slots is black makes me think that maybe I have to use that one for the 1024, and the blue ones for the 512. But on the other side, 2 slots are very close to eachother and the third is on its own, so maybe the 1024 has to be put into that slot 3.
the asus manual doesn't tell me very much, and I guess the position may be quite important for the dual-channel feature. I hope I maybe explained myself a bit better. Thank you.

[poppy]

Took the following quote from a review at http://www.driverheaven.net/reviews/asus/index.html:

The memory slots are much closer to the chipset than other motherboards in order to facilitate having a higher memory speed and timing option. The less distance that the signals have to carry with the least noise is what allows the NVIDIA nForce2 platform to reach DDR400 specifications and allow their DDR333 memory to run at the fastest possible memory settings. The memory is once again in a 2x1 configuration for a total of 3 memory slots, slots 1 and 2 for DDR channel 1 and slot 3 for DDR channel 2. In order to get the best performance, having identical sticks of RAM in slots 1 and 3 is required.

Hope this helps.

[zakimort]

so, having 2 512 and 1 1024, i should put them:
slot1 = 512
slot2 = 1024
slot3 = 512

but then if slots 1 and 2 are for DDR channel 1 and slot3 for DDR channel 2, I will have channel 1 with 1536MB and channel 2 with 512MB.
Aren't the 2 channels supposed to have same size?
Now I am even more confused.

[cros]

I'd say it doesn't really matter. Doubt you'll notice a difference. I'd follow the 1 and 3 rule, but then again, maybe I wouldn't.

Oh wait, I know what I would have done. See, I wouldn't have read that info listed above, and I would have just put the big one in the one to the left just for organization.

[zakimort]

Having tried both configurations, I thought it would be a good idea to post the results even if this thread is a bit old.
At first I tried the identical sticks in slots 1 and 3:
1 = 512
2 = 1024
3 = 512

It gave me an error on first boot. Rebooted and it was ok, then rebooted again and gave me error again. CPU speed was set on 100MHz safe mode.

So tried the second configuration:
1 = 1024
2 = 512
3 = 512

and is working perfectly.

I really have no idea why this happens, read and re-read the motherboard manual just to be sure, but it is stated that ANY configuration should work... anyway thank you for your kind replies, I didn't post earlier because the stick was delivered yesterday.

[COMPMASTER16]

That is very Odd, But ive had it happen, On a Old Pavilion 8665c with a P3 @650 mhz, It the Mobo allows a max of 256 MB ram, But only in a certain order would it allow 383, 1 256 card and 1 129 card, Put em in one way, it wouldnt boot, Switch left to right and it would boot and run fine...