3GB Ram combination

So I've been thinking about upgrading my ram from 1GB to 3GB. My MOBO has 4 ram slots and I'm pretty sure it has dual chanelling. I already have two 512mb DDR2 PC2-5300 chipsets plugged in and my question is: if I have a pair of matched 512mb ram is it okay to have another pair of matching 1GB chipsets. I know your not supposed to have e.g. a 1gb and 512mb in one dual channel but I am not sure how it goes in seperate dual channels.

I use:

Windows XP 32bit (SP3)

MOBO: Gigabyte GA-8I915PMD

P.S I have heard that XP SP3 can run with 3GB ram but it also depends on the motherboard. I can't find any info on my motherboard so I would appreciate if someone could tell me if my MOBO is compatible with 3GB

P.S2 On the crucial scan it states that I should not exceed manufacturer supported memory but I don't even know mine. So does anyone know where I can find it (I don't have any manuals etc. so I'm asking if I can find it witihn the system) and is really that important.

Thanks

You would be better off buying 2x2GB

Like this: http://www.newegg.com/Product/Product.aspx?Item=N82E16820134730

I really appreciate the responses :)

One more question:

Is it better to have x4 512mb RAM or x2 1gb / x4 1gb or x2 2gb (I am askin for both as I'm not sure if I'll be getting 2 or 4 GB)

I really appreciate the responses :)

One more question:

Is it better to have x4 512mb RAM or x2 1gb / x4 1gb or x2 2gb (I am askin for both as I'm not sure if I'll be getting 2 or 4 GB)

Nuteater

2x2GB or 1x4GB are preferable. You won't be mixing RAM which can cause problems even when they are the same speed and voltage + 2 sticks is generally a little bit more stable than 4 sticks.

How is it with having just 1 chipset ??

And also if I left that pair of 512mb and have just 1 chipset of 1gb on the other dual channel or would it be better to just have x4 512mb

I have decided that I'm getting 2gb not 4gb

How is it with having just 1 chipset ??

Nuteater

Roughly the same but you lose dual-channel.