How to buy the right Graphic Card--Guide and Suggestions

You really are confused regarding the purchase of a new Graphi Card for your system isn't it? And want the best bang for buck performance from it as you are a bit tight on budget in no matter which segment of gaming you are aiming at?
If the answer to the above questions is yes then you are in the right place, today at Computers and More I'm here to solve your dilemma regarding the various comprehensions revolving around how to get the best Graphic Card for your rig.
Lets start with the basics to the most intricate of details.

The name is enough  

The ultimate performance indicator of any graphics card is its model number, which represents a combination of graphics processor (GPU), clock rates, and memory bandwidth. The format is brand name + model number, i.e. Radeon R9 290X, or GeForce GTX 780 Ti.

The point is that a flashy factory-overclocked product with more RAM might look impressive, but you can bet it's grossly outperformed by a plain-basic specimen of the next higher model.
So when aiming for a GPU just see what is the highest model number you can get for your money, and by that I don't imply that you invest over 50K INR just to get a Nvidia Titan or the AMD/ATI R9 295x2 as they are not gaming cards but workstation GPUs.

Memory: Size doesn't matter--Bandwidth does

Selecting a graphics card because it has more memory is like choosing an exotic car based on the size of the gas tank. The unwarranted fixation on the amount of RAM is the biggest, most common mistake made by gamers looking to buy graphics hardware.
Unless you're running incredibly large resolutions (three monitors in surround or a 4K display), you don't have to be concerned about the quantity of RAM. If you're playing at 1920x1080 or higher you should be looking for a high-end model in the first place, and that will come with more memory by default.
What you need to pay attention to is bandwidth. While bandwidth expectations will vary depending on a graphics card's price and performance tier, always remember this: GDDR5 memory provides twice the bandwidth of DDR3 at the same clock rate. Since memory bandwidth is a significant performance determiner, choosing GDDR5 is a no-brainer.
Just remember this: when it comes to graphics cards, 1 GB of GDDR5 is infinitely preferable to 4 GB of DDR3.

Keep in mind the whole Platform

The graphics card is the most important component in a gaming PC, but the rest of the system is a factor, too. It's important to be aware of your platform's limitations.
Are you running an older dual-core CPU, like a Celeron, Pentium, Sempron, or Athlon X2? If so, it won't keep up with the high-end graphics hardware, so don't waste your money. Go for a mid-range card and save your hard earned dollars, or if you want the best game performance, upgrade to a modern processor that can handle four concurrent threads.
Your display is also an important factor. An older 1280x1024 monitor does not require the most expensive graphics hardware. Conversely, if you plan to run three 1920x1080 monitors in surround, a midrange model won't give you the framerates you want in modern 3D games.
Know your goals, consider what types of games you expect to play, align them with the rest of the platform, and consider other upgrades if necessary.

One is better than two

Both AMD and Nvidia offer a feature that links multiple graphics cards together to increase performance. This feature is called CrossFire on Radeon graphics cards and SLI on GeForce cards.
It sounds like a great idea, but scaling performance by multiplying GPUs isn't a smooth proposition. A second graphics card doesn't increase performance by a factor of two; it's more realistic to expect a 25-50% increase. That advantage diminishes even further with three- and four-GPU configurations. In addition, Multi-card setups can suffer from inconsistency, incompatibilities, and micro-stuttering. They also leech lots of power and can generate a lot of noise.
Don't get us wrong, when it comes to triple-monitor resolutions and 4k displays, multi-GPU setups are a necessity. On a single 1920x1080 monitor, though, it's overkill. Avoid the whole mess with a single high-end card

Compatibility

It's the ultimate buzz-kill: you excitedly open your case to install your new graphics card, and it's a half-inch too long. Before putting money down, take a moment to measure how much physical space your case has to offer.

Your power supply is just as important. How many six- and eight-pin PCIe power connectors does it have? How many watts is it rated for, and how many amps does it supply on the 12 volt rails? Cross-reference this info with the graphics card you want to buy. If your PC can't handle it you'll have to look for a card that will work with less juice, or consider a power upgrade.

When shopping for a better power supply, keep in mind that a trusted brand name (like Corsair, Antec, and Seasonic) is far more important than the maximum wattage as advertised on the package. This is because less-reputable PSU manufacturers are known for listing the tenuous peak output rating, not the maximum sustainable power output. In general, if a power supply has a good brand name and sports compatible PCIe power connectors for the graphics card you'd like, it will be fine. If you want some headroom for future upgrades, find a power supply that can accommodate twice as many PCIe power cables than your graphics card needs.

So you are all set to buy your new GPU with these basic guidelines but still if you have any confusion then feel free to leave your query and I'll answer to it ASAP. Also any addition or suggestion for improvement regarding the same is always welcome.