I have a Dell Inspron 8200 laptop and I am thinking of upgrading for wireless but I am not sure if I should get a Mini PCI wireless Card put in side or get a wireless card for my PCI card slot on the side? What would give me better performance? What would give me the best speed? What would give me the best quality?
 
"I am neither enemy nor friend, Iam back from the world where such words are meaningless"-Gray Fox(Metal Gear Solid)-

Really depends on the card and the implementation of the internal antenna cables.  There isn't a one is better than the other scenario.  I'd recommend the internal merely because it's more convenient and asthetically pleasing.  Its a PC Cardbus or PCMCIA slot on the side by the way.

Speed wise they are all mostly the same these days, range wise I found Hawking HG and DLink to be the farthest, USB or PCI do not matter for speed (as long as it is a USB2 type), convenience wise Cisco Aironet a/b/g is the best, because it has one of the best ranges and at the same time is a slimmest one out there so I can use my USB2/Firewire card on the top of it. Quality.. you can not beat Cisco, but it is at least twice as much in price, so I prefer DLink after it, I had 650G one for almost 3 years, laptop was falling on it a couple of times, and it is still working (I like this card's utility the most by the way).
 
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hhmm ok it's just real my chose then since the are both about the same  
 
"I am neither enemy nor friend, Iam back from the world where such words are meaningless"-Gray Fox(Metal Gear Solid)-