All I'm going to say is my personal experience with my 4870 card upgrading from a 7800GT.
I have been using both ATI/Nvidia cards for a long time now and go back and forth depending what's best value for performance at the time.
My Gigabyte 4870 came with the usual bundle ie cables,DVI TO VGA,DVI-HDMI,6 pin PCIe power adaptor to molex,Crossfire bridge etc...,CD with drivers (no games).
Installing the card was not without issues, however the main issue was with my old Nvidia drivers,basically after uninstalling via Control Panel and using DriverSweeper in safe mode,shut down PC after and installed my 4870 card. I still had 3 Nvidia DLL files trying to load at desktop(Nvidia you need to work on a clean uninstall of your drivers,in my case with Vista x64).
Anyway using Regedit I soon removed those without problems.
Installed the 8.6 hotfix drivers(I never bothered with the supplied ones on CD) I was impressed with the image quality and quietness of my 4870 card(I'm using DVI cable).
My card idles at 79/80c and can reach 92c when I run FurMark(great little program for stability/stress testing well beyond normal gaming) however it was rock stable and showed no artifacts.
I did play around with the XML fan profile hack but my fan gets loud above 31%,unfortunately I could not use the automatic setting with fan speed of my choice in the XML file, so had to use manual command,in the end I put it back to normal on automatic and 23% since I had no gaming/stability issues with various games I tested like Mass Effect,Oblivion,UT2004,Mythos,EQ2 etc..
My case cooling is 4x80mm (two fans blowing and two sucking,plus 120mm on my PSU ,gets cleaned by me now and then).
Once all the well known fan speed/OC programs have it working down the road then I'll play around with the fan speed again,I feel I don't need to use a third party cooler at this time.
Personally I think its a great card with very nice image quality,I feel however AMD/ATI set the idle fan speed a little too low and all their partners could of maybe included a decent free game ,however it has not effected my gaming or general use of the card.
I went with Gigabyte because of the 3 year warranty and price of the card in the UK(was lowest price I have seen here),choices here are Asus,Gainward,Gigabyte,GeCube,Sapphire,Club3D,HIS,PowerColor,basically everything expect Visiontek(not seen any listed in UK).
I give it 9/10 ,lost a point because of the above

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