Ring-a-Ding-Ding!

 is a quest in Fallout: New Vegas.

Quick Walkthrough
OR OR OR
 * Speak to Swank at the reception desk when first entering Tops Casino. Having a combination of 3 speech checks/bits of evidence Swank will distract Benny and let you search his room for evidence.
 * Speak to Benny directly.
 * He'll ask the Courier to wait in a presidential suite, and then flee; his bodyguards will be waiting in an ambush at the suite. You don't have to actually go to the suite; promptly leaving the casino will trigger dialogue that finishes the quest.
 * Passing a speech check of 60 convinces him to go alone with the courier to the suite where he'll answer questions before attempting to make a deal with the Courier.
 * Using a male-specific perk (Black Widow or Confirmed Bachelor) will grant addition dialogue choices that will convince Benny to go up to his suite alone with the Courier and have sex and kill him in his sleep, or attack when alone.
 * Confront Benny physically on the Main Floor. This will turn the whole casino hostile unless you've received Swank's help (two speech checks/pieces of evidence).  Having the Terrifying Presence Perk will grant a new dialog."I dug myself out of that grave to plant you in yours, Benny (Attack)".
 * Speak to Yes Man in the suite (13th floor behind the double doors) to find out Benny's plan and the significance of the Platinum chip.
 * Once the player has gathered the necessary information, leave the Tops.
 * NCR and Caesar's Legion will be neutral toward the player after this quest regardless of any past crimes committed. Representatives from both factions will approach the player with requests from their respective chiefs to parley.

Detailed Walkthrough
Now that you know Benny is at the Tops casino in New Vegas, it's time to go find him. You can deal with Benny in a few ways:

I. Speak with Swank. There is a series of 3 Speech checks (15, 30, and 45) and there are 3 pieces of evidence (Distinctive cigarette butt, Engraved cigarette lighter, note found in Novac Message: Khan hospitality). With 3 total checks/bits of evidence you can convince him that Benny needs to be taken care of. He'll give you Benny's Suite Key and return all weapons secured when you enter the casino. Find Yes Man in Benny's Suite and return to Swank. If you choose to take Benny out, Swank will send Benny to his room alone, where you can talk with him and also choose to kill him. This won't cause the casino to become hostile to you. There are other dialog options with Swank besides Benny needing to be taken care of, and other options like working with Benny when you talk with him. Note: Killing Benny in his suite, regardless of circumstances will not cause the casino main floor to become hostile to you (tested four times on Xbox 360). Additional Note: Also, after convincing Swank of Benny's treachery, receiving your weapons back, and examining Benny's Suite, you can take a [Hidden], silenced sniper shot at Benny from behind the front desk. His guards were not alerted, nor were any casino patrons or staff. Even after speaking to his bodyguards and looting his body, no one became hostile. Another viable option is to use a stealthboy, reverse pickpocket any explosive onto Benny, loot his body then leave the casino. Nobody was hostile upon returning immediately afterwards.

II. If you speak to Benny and choose the peaceful resolution options: No guards will come after Benny's been killed and casino will not turn against you; four guards will come if you forgive him and let him escape (they might appear in the suite a few moments after you've killed him, but won't attack, instead simply leave the room ). Note: When he was set free he takes off and he hasn't been seen since, so not sure where he goes exactly.
 * He will give you the key to the Presidential Suite and promptly send four bodyguards to kill you, fleeing the Tops Casino to The Fort.
 * If you pass the speech check of 60 to get Benny accompany you up to the presidential suite he will make you an offer. You can accept, kill him, or forgive him and let him escape.
 * If you have the Black Widow perk, it is possible to have Benny wait for you at the suite, where you can either kill him then, sleep with him then kill him in his sleep, or sleep with him and then fall asleep. If you sleep with him and fall asleep he will be gone in the morning and will have left you a note.
 * Benny will then be captured by Caesar's Legion. You will see him at the Fort and Caesar will give you the choice to decide how he dies or you can decide to help him escape. You only have two choices for his death; the first is crucifixion, and the second is battle him in the arena in a fair fight. If you decide to help him escape you will either have to kill all the Legion in the Fort, or give him a stealth boy and a bobby pin to help him escape. You must have a high sneak skill and a stealth boy for yourself or the Legion will become hostile. You can ask him what he will do if you set him free and he tells you that it's your choice; he can either take over the strip at your side or he will walk off into the sunset and never see you again. However it doesn't give you a choice to pick one or the other after that dialog; you can only kill him or set him free. Caesar will also give you the platinum chip and he will ask you to destroy everything mister house has made. After that you can leave the fort but only without the platinum chip. Or you could try to steal you weapons back and try to escape somehow.

III. Physically confront Benny on the main floor of the casino. If you talk to Swank beforehand and provide two speech checks/bits of evidence he'll return your weapons and insure the chairmen stay out of the fight. Without his help the entire casino will turn against you.

Speak to Yes Man/Swank to conclude the quest.

Remarks on I and II After talking to Yes Man, you can speak with Swank and choose to take Benny out. The courier will need to head straight to Benny on the main floor of the casino. He may be on his way to his suite, but you may still be able to speak with him. If you want to gain a few extra caps before killing him, choose the Barter check of 35 and you can get 500 caps and 250 casino's chips. He will ask you to go to the presidential suite. After the dialogue, you can kill him immediately without making the casino turning hostile to you. If you are lucky and his guards are far away, his guards may not turn hostile either.

Outcomes:

I. If Benny was killed, Swank becomes the new boss and the platinum chip is recovered.

II. If Benny escapes with the chip, he will later be caught by the Legion.

You always get the Presidential Suite Key, either during the quest/found it on Benny's corpse.

After speaking with Yes Man, you will have another option for New Vegas, opening up the Wild Card series of quests.

If you choose to let Benny live and escape the Tops Casino, but don't wish to help Caesar, you can start the Legion quest so Caesar gives you the chip and kill the guards at the entrance to escape with the chip. This will make you vilified among the Legion, however.

Also if you have a sneak level of fifty you can sneak in a .44 magnum ( with a scope) and there is a set of stairs that you can go up halfway and snipe Benny out. Do this before ever talking to him and only his chairman bodyguards will become hostile towards you instead of the whole casino when attacking is prompted in the dialog. Loot all their bodies giving you the platinum chip and a silenced .22 sub machine gun and Maria... Then just walk out like nothing ever happened

Bugs

 * If you choose to wait for Benny in the presidential suite, nothing may happen after going up to the Presidential Suite. What should happen is a call from Benny at the intercom stating: "Baby, this meet and greet of ours?  Chalk me up for a no show," followed by a short dialog and an ambush by four of the Top's bodyguards.
 * The ambush may never happen. Instead, walking towards the elevator triggers a message from Benny: "The cleaners will knock twice. Make sure they're thorough."  This allows further dialogue, but the ambush may never have happened.
 * Choosing the dialog option "Lets make a deal" while in the Presidential Suite causes Benny to reward the PC (Player's Character) with 250 caps. If further dialog with Benny is chosen, he will reward the PC with a key to the "Top's Suite."
 * If you talk to Benny in his room and choose the option "Player says goodbye" he will give you 250 tops chips. This can be repeated as many times as the player wishes.

Behind the scenes
The title of the quest is a reference to Frank Sinatra's 1961 song Ring-a-Ding-Ding.