Two questions regarding power supplies and Virtual Memory

Hi, I own an hp pavilion dv4000 laptop, with no system upgrades and the basic 915 gm/gms 910 gml chipset. The power supply it came with is only 65w, which seems ridiculously low, however some of my friends have been saying that laptops generally come with a power supply efficient enough to run the computer to the maximum of its potential and buying a new one won't increase performance. Is this true or should I consider getting a new PSU?

Second, RAM, I have 512 mb ram, however in the system properties it only says 504 mb, and in dxdiag it says 502 mb. At first I thought it was my video card integrated, but my video card is 128 mb. What is siphoning off that 8-10mb?

Thanks!

Edit-yeah, the title says "virtual memory," I meant RAM

The power supply should be quite adequate for your laptop. If it didn't get enough power already it would most likely just crash or reboot randomly.

As for the odd amount of RAM: it's a laptop; most likely some integrated component other than your video card (sound card?) needed a few megabytes of RAM and HP found using a little bit of the system RAM cheap (and space-efficient).

If you checked DxDiag while a game is running with large amounts of textures (i.e. Guild Wars), likely it would say even less than 504 or 502MB. I think when it says you have 128MB of video RAM, what it means is that you have 128MB of "Shared" RAM.. meaning it will borrow up to 128MB from your system's RAM for graphics, as needed.

As for your PSU, 65W is likely all it needs. A "lite" laptop processor is designed to draw little power, you have no seperate video card to suck power, and the vast majority of the rest of it would power your screen anyway. And like lordpwn said, if there weren't enough power you'd have serious system problems.