nvidia very good for gaming, i use nvidia has long 
For gaming purpose i will vote nvidia, for mining i will vote amd
can u give me recomendation NVIDIA card with budget around 50$
i want to build a gaming PC, or is that 50$ not enought??
$50 for a graphics card for gaming is not enough
You need a bigger budget.If you want to game, your graphics card is probably the most expensive component in your pc.
so! what budget do I need to get vga for gaming??
right now I only play Dota on my PC, at least pls recomend me what VGA do I need to play it well
coz I am so clueless about VGA, never have one myselfTo properly answer your question you need to include a bit more information:
- What CPU do you have, or are looking to buy?
- What resolution do you want to game in?
- Will your monitor support this resolution, or are you upgrading this to support your new GPU?
- Where in the world are you located?
1. i used an old PC with Core 2 duo CPU 3 ghz
2. 1366x768, this is my monitor resolution
3. I dont plan to upgrade monitor
4. I am indonesia
This thread will give you some ideas:
http://www.tomshardware.com/answers/id-2559863/desktop-build-dota-max-settings-60fps-1366x768-resolution.html
From that thread, I'd be looking to purchase a Nvidia GT 730 or equivalent. They can be picked up for around $85 AUD.
If you're going to upgrade your PC in the near future though, I'd recommend buying something mid tier like a Nvidia GTX 1050 / 1060 or an AMD RX 460 / 470 to get better longevity from the card.