I might buy a desktop that has a dedicated graphics card AMD HD7470 2GB and also has an on-board graphics AMD HD7420 2GB UEFI and the two together gives 4GB.
I've researched on the two boards but can not find anything relevant about them. I would appreciate if say are good for gaming.

Thank you!

Sorry if English is not right*

Without even opening up a search engine, I can tell you they are not good for gaming. They might run SOME games on low-medium settings, but for a good experience, you are looking at something more powerful like HD7770, HD7850 or higher.

What would you like to know why there is no information (Core Clock, Memory Clock, etc.). I had a computer and was under warranty, and he broke down and may have to choose another store and the only one that has a good price and better than my PC is this.

Intel Core i5-2320 3.0Ghz Turbo 3.30GHz
CHIPSET Intel B75 Express
6GB RAM (I have 4GB, 10GB makes total)
1TB Hard Drive
AMD HD7470 2GB Dedicated
AMD HD7420 2GB UEFI On-Board
The two together have 4098MB (4GB)

and I would compare the graphics with my old pc, which was a NVIDIA Geforce 405 1GB Dedicated. If both 7470 and 7420 is as Geforce 405 was already good.

I think hardly anyone knows details about the two graphic cards.

There is enogh info if you look hard enough. What Zipsi said is the bottom line. If you want to play modern games at a reasonable framerate then you need a better graphics card...and one graphic card can handel that with less headaches than two. Check the cards for yourself >  http://www.videocardbenchmark.net/high_end_gpus.html  (start at the bottom of the list and scroll up)

Intel I7 960 @ 3.87ghz *Intel DX58SO *HIS HD6970 2gb *Corsair TX650M *2x4gb Corsair XMS3 *WD Black 1TB *Windows 7 Home Premium 64bit *Gateway HD2401 24" 2ms 1920x1200  ***Asus N71Jq laptop *Intel I7 720QM Processor *Mobility Radeon HD5730 1gb *8gb Ram *Windows 7 64bit  ***Acer 5750 laptop

* A clear conscience is usually a sign of bad memory *

Thank you both. From what I saw in 7470 is better than the Geforce 405 that I had on my old pc and I could play well FIFA 13 / GTA IV. If it is better than my old and if I use it with 7420 at the same time should give the games I want.

Really?  Good luck with that.

Intel I7 960 @ 3.87ghz *Intel DX58SO *HIS HD6970 2gb *Corsair TX650M *2x4gb Corsair XMS3 *WD Black 1TB *Windows 7 Home Premium 64bit *Gateway HD2401 24" 2ms 1920x1200  ***Asus N71Jq laptop *Intel I7 720QM Processor *Mobility Radeon HD5730 1gb *8gb Ram *Windows 7 64bit  ***Acer 5750 laptop

* A clear conscience is usually a sign of bad memory *

I will buy a pc with a Geforce GT630 2GB.

why would you buy a PC with such a pathetic video card if you want to game.

I5 3570K@4~5.0ghz: Gigabyte GA-Z77X-UD3H:Corsair Hydro H70w/Delta 240CFM Fan: 16GB Corsair Vengeance DDR-3 1600: 2 XFX Radeon 7950 @ 1150/1575 : Corsair AX 860 PSU: x2 WD Black 1TB HDD's: 90GB OCZ Agility 3:CL X-FI:Corsair 500R Arctic White Edition:3 22inch Asus monitors Eyefinity @ 5294x 1050(bezel comp) : Alienware Tact-X Keyboard: Naga Razer gaming mouse:Corsair Vengance 1500 Headset .

I already have a computer with a Geforce GT 630 and is a nice graphics card. Better than I thought.