Get wise, follow my advice

Important factors to be kept in mind while deciding on the brand, when you go out to buy a

• Laptop: priority 1: hardware warranty. In-home service is important. Most of the brands provide remote diagnosis only(telephone assistance), and in case of hardware technical problems, you have to visit their service center for repairs.Dell and HP are some exceptions. In this respect Dell scores high as it provides Full cover(protection against accidental damage).
  priority 2: weight. Laptops/Netbooks are meant for portable computing, they should weigh very less. So, never go for a 17-inch laptop, its really bulky.
  
  Best performers: Dell 14 and 15 inch laptops
  
• Graphics card: priority 1: Quality matters more than quantity. GPU, shaders, memory frequencies are the 3 important specs to see while choosing a graphics card. So a 256MB (say) card with much higher specs(mentioned above) will outperform a 1GB card with lower specs.
  Note: check the connection type. PCI Express cards can't fit in AGP slots and vice versa, so check what your PC can accommodate before you buy. The PCI Express, also known as PCI Express x16 offers performance as much as 4x faster than AGP 8x bus. Nowadays PCs have at least one PCI Express x16 slot type.
  
  I recommend: AMD Radeon HD6990(for desktops)/6990M(for laptops), Nvidia GeForce GTX590(for desktops)/GTX580M(for laptops)... ultimate GPU, for desktops, very costly
  
  ATI Radeon HD5870(for desktops)/5470(for laptops), Nvidia GeForce GTS450(for desktops)/GT550M(for laptops)... great performance, costly
  
  ATI Radeon HD5570(for desktops)/550v,4570(for laptops), Nvidia GeForce 410M(for laptops)... good performance, affordable