Can i replace my Graphic Cards with good ones?

My Laptop is a Dell Inspiron R15,
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Windows 8.1
Intel(R) Core(TM) i7-4500U CPU @ 1.80GHz 2.40GHz
8.00 GB (7.88 GB usable)
64-bit Operating System, x64 based processor
No Pen or Touch Input is Available for this Display
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With all of that, Aion (An MMoRPG) and Tera (An MMoRPG Too) work with less than 20 FPS, it really sucks and i bought this Laptop for 999$, while my friend who bought his Laptop for 800$ can run games very smoothly, and i found the reason was, my Graphic Cards were Weak, and his were Strong, even though his Laptop is Cheaper, here's my Graphic Card
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AMD Radeon HD 8670M
Intel (R) HD Graphics Family
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I Really regret buying this Laptop, i thought all what matters for gaming is Processors, so i picked a i7 with such weak graphics, not knowing graphics would effect the gameplay,
so i wonder is it possible to replace the Graphic Cards in a Professional Place that sells Laptop? And if not, is it possible to replace the Laptop with another one for one with paying less than 100$?

Gaming laptops start at around $750.

The importance of components is exactly the opposite of what you thought. The graphics card is much more important than the processor when gaming. Making the pictures on the screen is where all of the heavy lifting occurs.

Almost all laptops have graphics which are NOT upgradeable. Those that do are high end gaming laptops and they will say that they have a MXM slot for a graphics card.

*IF* you can return the one you got, I believe you would be very happy with the Lenovo Y510p. There were a couple of these at Lenovo's site which were marked down significantly to $899 or so. They have dual 755M graphics cards in SLI for outstanding graphics performance. Just make sure you don't get the basic model because I believe that only has one graphics card. Go to Lenovo.com and look them up.

Depends on the type of laptop your friend has, i found in some cases some cheaper laptops run better than the expensive ones could also be his graphic card settings is why the game is running smoothly, that graphic card is soldered to the motherboard best to buy another laptop with a better graphic card suggest the nvidia gtx or gt series

The rule of thumb is not messing up with laptop video card change.

I don't think dell is extending support on replacing g cards in laptops
the graphics card present is an ideal one for gaming

But this is a good graphic card model. But it would be too costly to buy new graphic card