Memory upgrade for Dell Studio XPS 435t/9000

[Giulio]

I recently had to replace my main hard drive due to critical error codes. When I did that I noticed that my video card was extremely filthy, which explained why my monitor would go into power save mode. My system is now working fast and much quieter. Not bad for a rookie techie.

I now have the itch to try and make it better, if possible.
It has 12 Gb (6 x 2Gb) of ram. Would it make much of a difference if I was to upgrade the ram.
From what I have read, the maximum amount of ram for my system is 24 Gb. But I have also read that the maximum amount of ram for Windows 7 Home Premium is 16 Gb. So which is it?

Also the board has 6 dimm slots, 2 banks of 3. So the modules have to be installed in 2 groups of three similar modules, correct? For example 2,2,2 and 4,4,4 for a total of 18Gb. This is what I am planning on if 16 Gb is the max. Or 6 x 4Gb if 24 Gb is the max, and if I con myself to spend the money.

I found these which have the same specs as the modules I have now:
http://www.memoryupgradecompany.com/memoryupgradedetails.asp?part=80569-11805&MnfId=&MdlId=8111022673

Am I limited to these specs?

So, is it worth it? I do a lot of video editing. My son does some gaming.

Dell Studio XPS 435t/9000
Intel Core i7 920 @ 2.67 GHz
0x501H main board
12 Gb triple channel ram DDR3-1066 PC3-8500 240-pin DIMM
ATI Radeon HD 5770 video card
WD 1 TB main hard drive
Seagate 3TB storage hard drive

 

[Emerald]

the motherboard can address up to 24GB of memory but the OS will only use 16GB max.

I am not sure if the additional 4Gb of memory will help you with the video editing but I know it will not make any difference for the gaming.

in addition, you should get a set of triple channel since they are tested together and not three single memory sticks.

 

[Giulio]

Thanks Emerald.

Crucial has this as compatible with my system:
12 GB (3 x 4GB) DDR3 PC3-12800 • 9-9-9-24 • Unbuffered • NON-ECC • DDR3-1600 • 1.5V • 512Meg x 64 •

My ram is:
DDR3 PC3-8500 NON-ECC DDR3-1066 ($71.99)

Do the bold numbers, I assume they represent speed, have to be the same?
What basic specs do I need for compatibility? Just DDR3 240-pin PC3 NON-ECC?