New to hardware? Different clock speeds and different brands. EVGA has a step up program. BFG has great customer support and RMA. MSI dont get it. XFX Extreme edition has a higher clock speed and gives higher performance. Personally it's easier to pay less and overclock
XFX is just a company that makes video cards based on nVidia's graphics chips. XFX just uses nVidia's GPUs, solders them to a board designed and manufactured by themselves, and sells it. eVGA, MSI, BFG, these are all companies that make video cards. nVidia does not make any of their own cards for retail.
XFX often produces overclocked cards that run faster than stock variants and sells them for a price premium. If you only paid $25 extra, it's probably not a bad purchase. Just depends on how much it's overclocked versus how stable it is versus how much the stock version would cost.
Each brand doesn't has much difference between others since they produce the same card with the same chip. The only difference is the pre-overclock one compare to the standard clock one. But there is a price premium that you have to pay for the pre-overclock one.
IMO, when choosing over brands, you need to know which brand company provide the best customer services, RMA policy, longest warranty of product etc etc...
If you live in the US, EVGA is good since they have the step up program. XFX also nice since their products is lifetime warranty, Gigabyte has 3 years warranty etc etc...
XFX has the double lifetime thing which would come in handy if you plan on selling it at a later time(like on ebay or something). The warranty transfers over to that person. EVGA has a lifetime warranty and the stepup program. bgetter card comes out, all you do if pay the difference but it only lasts 90 days
XFX Extreme edition card is overclocked. XFX XXX version is also overclocked(if they arent the same thing)
EVGA has superclocked. thats overclocked for them. they also have a superclocked KO which is clocked even higher
BFG has OC and OC2 cards which are overclocked. BFG are very expensive though.
Go with EVGA IMO. Great service and great products
I've got had 2 XFX boards( a 7800gt and 8800gts) and both have been great. One of my friends went through several EVGA 7800s before he got a good one. This could all be luck of the draw but I'm sticking with XFX.
The cool thing about a factory over clocks is liability. If you over clock and burn something up it is on you. If they over clock and it burns up at their set speed it is on them.... So long as the factory OC is not much more money than the stock speed card I'd rather have the liability on them.
PS it might be a good time to wait a week or two. New cards are just about to come out. That 8800GT looks really cool...