i have laptop COMPAQ PRESARIO CQ42-263TU..what is the best videocard for this laptop because my videocard is GMA 4500M..it says it better for office use only but it is the slowest for 3D games..so that i decide to change my videocard..can you give me some advice what videocard is the best for my laptop..
In reality, you can change or add any video cards on a laptop but thats for alienware types and/or BIG laptops (17-18inch).
In your case im afraid there is no physical pci-e slot available on your motherboard (even if you look at PC wizard or Sisoft Sandra there will be available PCI-E lanes/slots you will see) to install a video card in nor does it have cooling for it or even would it fit in the case. You are pretty much stuck with Intel GMA 4500M. Only choice is to buy a "gaming laptop".
Whether you want a dual or single graphics card setup, your best bet is the 8800 GTX by Nvidia. It's the most feature-rich (DirectX 10 compatible) and highest performing (highest frame rates). Some of the manufacturers for this card are EVGA, BFG, and Foxconn, just to name a few. Physically, all the different brands are nearly identical.