How much RAM could my laptop handle?

I'm usually tech savvy but when it comes to laptops and their ram compatibilities I'm not exactly the first person you'd come to.

I own a Asus X5EA Laptop, 4GB RAM, 500GB HDD etc etc.

Does anyone know if my laptop could take anymore ram, i.e upgrading it to 8GB?
I'm soon to purchase an Apple iMac 27 for my image and video editing and would like to keep my laptop for editing on the move.

I'm running Windows 7 64bit, Photoshop CS5, Sony Vegas Studio 9 Pro and I word process a lot so my ram is taking a battering when I'm using big files.

So any help towards finding out the maximum ram it's able to take would be very highly appreciated.

Regards,
TripleB92/Ben

**EDIT**

Seems like they gave me the wrong bloody model number! It's infact a K51AE

 

Spec sheet for the K51AE says max memory of 4gb, so you're at the limit.

 

However, spec sheets are only printed to what is readily available and thus tested by Asus when the model is first released; Asus does not go back and update max RAM as the stick capacity increases over time. This has a well known history around here way back when 2GB sticks were as rare as 4GB sticks were last year, and everyone here was posting whether Asus' would work with 2x2 or 2,1. It is possible that the K51 might work with 4x2 or 4,2 but you'll have to try it or find someone who already has this config.

The bigger question is whether the software you're working with can/will take advantage of the 8GB, and (for me) the inconvenience of editing projects using software on two different platforms. Buying an iMac 27 just to run W7 software only is silly, as there equal or better quality prosumer monitors that can be had for less, or even the Apple Cinema Display.

PS the X5xx and K5xx series are the exact same thing, just labeled differently for release in different global markets.