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What the hell is it, and yes ive googled, but im a simpleton.
Do i need it? Can i use it?
What is Mantle? Check this thread.
You can definitely use it with your setup and you will get a big fps boost and your gameplay experience will be improved greatly. So far Mantle works in two games, Battlefield 4 and Thief. Two further games are launching with Mantle support this month, Sniper Elite V3 and Plants Vs Zombies Garden Warfare. There is also a Mantle benchmark called StarSwarm. 20 other Mantle games are in development and will be released over the coming months. See the thread i linked above for further info.
Can I also use it with this GPU: Gigabyte Radeon R9 290 Windforce?
Ok so you say it works for me.... now how do i get it? Sorry to be a noob!
Sniper Elite V3 third time lucky it might rock I Hope so!

Can I also use it with this GPU: Gigabyte Radeon R9 290 Windforce?
What the hell is it, and yes ive googled, but im a simpleton.
Do i need it? Can i use it?
1. You certainly don't need it as its something you have never missed.
2. Don't go buying a 290 just for 2 games and 90% of the games in development would never be bought anyway. Plants Vs Zombies ? really ?
3. You can use it, but I'm sure i read the 7950's are horrible in BF4, that may be fixed with newer drivers though.
4. Thief doesn't need Mantle.
5. For the love of god, do not go buying games just because you can use Mantle.
6. Read point 5 again.
7. Read point 6.
8. Mantle is an AMD product... i.e. It will be broken forever, it will need patch after patch, and in the end, it promises so much and yet after months and months its delivering nothing.
9. Like Freesync, there is only a few cards supported.
10. Read point 7.

Yes that would work with Mantle
...
Yes.
Nope. They work very well.3. You can use it, but I'm sure i read the 7950's are horrible in BF4, that may be fixed with newer drivers though.
8. Mantle is an AMD product... i.e. It will be broken forever, it will need patch after patch, and in the end, it promises so much and yet after months and months its delivering nothing.

think im leaving AMD for good. Not sure they are up to anything that i can use any more. Will sell my 7950s and be done with it.