Nope, Not as good as the C4THY
That is a decent deal, but an Ati 5850 is still a relatively powerful graphics card, they can handle all of today's games maxed out, I don't understand why you would want to upgrade?
yes
The ATI 5470
Yes, it is a good card for (new) games.
CrossfireX (double) the ATI Radeon 5870 or the Nvidia 295
I'm running an ati radeon hd 5850 and it can handle both of them at max settings with no stutter however newer models of it aren't as good. I recommend a 5870 (the model above) however see if you can get your hands on a 6950 it is a very worth investment as it has the same hardware as a 6970. You can flash it and run it as that instead. MY RECOMMENDED CHOICE: ati radeon hd6950
Generally any good quality aftermarket cooler will do better than ati's stock standard gpu cooler, so i'd say unless your going to be overclocking your temps will be fine
Yes, this card will play doom3 and performance will be good for a mid range card.
There are hundreds of ATI and ATI-based graphics cards, so it is impossible to give you any sort of description or specifications without a model number.
the most high end graphics card from ati is the hd4870 x2 which is basically just 2 hd4870s in one card
it depends which version your talking my ati Radeon hd 3450 is a 512mb 256bit card but most of the ati Radeon 3450s out there are 512mb 64bit
According to the Oblivion website you need to have an ATI X800 series, Nvidia GeForce 6800 series, or higher video card. Here is a list of supported video card chipsets. However you can still get the game to work if your card is not listed here. * ATI X1900 series * ATI X1800 series * ATI X1600 series * ATI X1300 series * ATI X850 series * ATI x800 series * ATI x700 series * ATI x600 series * ATI Radeon 9800 series * ATI Radeon 9700 series * ATI Radeon 9600 series * ATI Radeon 9500 series * NVIDIA GeForce 7800 series * NVIDIA GeForce 6800 series * NVIDIA GeForce 6600 series * NVIDIA GeForce 6200 series * NVIDIA GeForce FX series