Okay first i want to know how much more ram i can put in it?

and secondly, will the ram need to be specific to my laptop, or are they pretty much the same spec nowadays? i bought 2 gb of ram 3 months back for my dell inspiron 1300, can i put these in the samsung? the spec for my laptop is below.

* Intel Core 2 Duo T6400 processor.
* 2.0GHz processor speed.
* 2MB cache.
* 4GB DDR2 RAM.
* 15.4in screen size.
* Resolution 1280 x 800 pixels.
* Widescreen.
* 320GB SATA hard drive capacity.
* Multiformat dual layer optical drive.
* Intel GMA X4500 graphics card.
* 128MB graphics memory.
* 3 in 1 media card reader - compatible with SD, MMC, SDHC.
* 3 USB ports.
* 1 HDMI port.
* 1 Ethernet port.
* 2 x 2 watt speakers.

* 1.3Mp webcam.
* 802.11b/g wireless enabled.
* Windows Vista Premium operating system installed.
* 3.5 hours battery life.
* Size (H)3.63, (W)35.8, (D)26.5cm.
* Weight 2.7kg.

thanks