Big Winner, Atomic Wrangler

Big Winner, Atomic Wrangler is an unmarked quest in Fallout: New Vegas.

Quick walkthrough
You need to play the games that the casino has to offer (Blackjack, Slots and Roulette) until you are banned from gambling in the casino. You can be banned by winning too many games and getting too much money from the casino. During this process, you will be receiving three different prizes from the casino. Each prize will be given after you win a certain amount of money while gambling. These prizes are usually given by the table manager of the casino.

Detailed walkthrough
As you win the games the casino has to offer, you will be receiving the rewards below after reaching its money target:
 * 1,250+ chips: beer
 * 2,500+ chips: whiskey & dapper gambler hat
 * 3,750+ chips: absinthe, Rum & Nuka & dapper gambler suit

After earning 5,000+ chips, you will be banned from playing games in the Atomic Wrangler casino. You can still use its other functions, like the bar and the services of the prostitutes (if the Wang Dang Atomic Tango quest has been completed), but you cannot gamble on its tables anymore. This ban is permanent.