The time has come for me to invest in a new graphics card, I currently have a GTX 560 Ti. I was going to go with the Gigabyte GTX 760 4GB OC card. But since the store I ordered it from just changed their status to not selling it anymore (previously their status was orderable).
So the new cards I'm looking at (higher price range) is ASUS GeForce GTX 770 4GB DirectCU II OC and Gigabyte GeForce GTX 780 GHZ Edition 3GB.

Some advice about which card to go for would be much appreciated.

Simple advice is to get the best one you can afford - after making sure it is compatible with your motherboard.

You can find out a lot by typing the card # with the word "review" at the end into google. Generally the higher the number the better on the specs.This does not apply to the card # itself as those are very confusing.For example shader version 5 is better than shader version 4. Also what Draclvr says is important because some companies might make the card in a single slot version and some in a double slot version so check the room.

And you can compare cards at http://gpuboss.com/

While new graphics cards are always nice - what exactly are you playing the your 560 Ti is lagging on?

I was wondering that too, Inland. The 560 Ti is a very nice card.

I was wondering the same thing. I haven't encountered any problems with the GTS 450 that I got with the computer I bought from eCollegePC. It turned 4 years old last week.

My current graphics card is the GTX 560 Ti and it's coped flawlessly with everything for the last three years

It's lagging on games like Tomb Raider and any heavy modded games like Skyrim and Oblivion.
But I decided to go with the ASUS GeForce GTX 770 4GB DirectCU II OC. Since it was quite a bit cheaper and the 4GB will come in handy with modded games. The other reason to why I went with ASUS this time instead of Gigabyte (as I always do), is that I don't trust the store which offer the cards at cheapest price.

Modded games can move large texture maps, so the additional memory should help. I'm running a GTX 460 (2GB) card, and it does very well with the Tomb Raider games. Hope it works out for you

I never could afford the 2GB cards before, So I always played games with the 1GB version. Looks like the store finally sent the graphics card, but they lack all sort of skills when it comes to keeping you updated with the order status.
Thanks, I hope it works out well (have no experience with ASUS cards)

I think I have a similar issue now - I want to replace my good old Radeon HD5850 with something more powerful, like Radeon R9 285 or GeForce GTX960.

The problem is that I am worried about running some older games - mostly those from 2000s that requires 3D accelerator (more older ones run fine in DosBox/ScummVM/Windows 98@Virtual PC and newer ones should not be a problem).

Can somebody (who has recent cards) please confirm they work fine with older games - preferably those on CryoGen engine? Those are games by Cryo like Time Machine, Odyssey, Arthur's Knights, - or Arxel Tribe's games like Casanova! You see, they were the reason I have been faithful to ATI/AMD cards for quite some time as back in 2000s I could not get such games running fine on nVidia cards (6800/8000 if I remember it correctly) and had to exchange them for Radeons.

So, I've decided to install the new graphics card. But are there any more files that I have to uninstall except for these:

NVIDIA 3D Vision driver 350,12
NVIDIA 3D Vision driver and guidance unit 349,95
NVIDIA GeForce Experience
NVIDIA Graphics drivers
NVIDIA HD Audio Drivers
NVIDIA PhysX
NVIDIA Virtual audio