Fallout 1: Find the Water Chip

• Equip some weapons (You should have familarised yourself with the manual. It's a PDF file in C:\Program Files\Steam\steamapps\common\Fallout).
  
• Exit the cave (Use your map to find the way out).
  
• Walk towards the exit grid, then step on it.
  
• Click the button next to Vault 15. You will start to travel there automatically (WARNING: Time still passes when travelling. You only have 150 days until the water runs out). On the way, stop at Shady Sands.

YOU CAN BYPASS THIS SECTION AND HEAD STRAIGHT TO NECROPOLIS
• Before you reach Vault 15, don't go there quite yet. Instead, find Shady Sands. If you were lucky, you may have came across some guards with a merchant, who will take you to Shady Sands if you ask nicely!
  
• When you reach Shady Sands, talk to one of the guards, Seth. Barter or Steal a rope from him.
  
• Return to Vault 15, equip the rope, use it on the lift, then descend.
  
• Head west to another lift, picking up some more rope from a side room opposite the lift.
  
• Descend to Level 3 and find the destroyed Command Centre. You will gain 500 XP.
  
• Exit the Vault without a water chip. You will need to search harder for one of those.

YOU CAN BYPASS THIS SECTION AND HEAD STRAIGHT TO NECROPOLIS
• Get to The Hub. Find the librarian and Steal/Barter the Holodisk from her.
  
• This Holodisk contains data of some useful places.
  
• READ ME: To extend the quest deadline by 100 days, talk to the Water Merchants in the downtown area of The Hub. For 2000 caps, they will send water to Vault 13. In the unpatched version of the game,this will lower the time limitation of the mutant invasion on Vault 13 by 100 days.
  
• Head to Necropolis.

• Look for a manhole cover. Watch out for the feral Ghouls, though, as they will attack you. Click the manhole cover to go into the sewers.
  
• Head Northwest and talk to the friendly Ghouls. If they enquire about you taking the Water Chip, you can say yes and that you will fix it (RECOMMENDED) or say no. If they don't believe you, say you'll fix their water supply. You should fix it right away, but if you can't be bothered, you can come back 6 months (in game time) later to fix it.
  
• Head north-west until you can go no further. Climb a ladder, and if you end up in a room with a non-hostile Ghoul, then find a Super Mutant (Big, green, stupid). Otherwise, look for a manhole then get to the room with a Ghoul.
  
• Go down the manhole cover next to the Super Mutant, and look around for a pile of junk. You can use this to fix the pump.
  
• Next to the Super Mutant, there is a room. Walk inside.
  
• You'll be greeted by a mutant called Harry. Bypass him by saying "I'm a ghoul." This will allow you to access the water pump. If you fail the check, Harry will escort you to the Super Mutant base. You'll end up being interrogated by a mutant with a weird eye, The Lieutenant. He will probably put you in a prison cell, or if things go really wrong,they might tie you up and dip you into the vat of FEV. You can try to lockpick the door and escape, and sneak out (You may need a high lockpick skill for this). If you don't mind cheating,then you can save before you speak to Harry, and if you fail the check, you can reload and try again.
  
• You will see the water pump in the third room. If you have the parts, then you can fix it and avoid angering the ghouls in the Vault.
  
• OPTIONAL: Find the prison with a ghoul, pick the lock and free him.
  
• In the next room, in a small cell, there is a entrance to Vault 12. Make your way through it. You may have to fight some Glowing Ghouls.
  
• Reach the Water Chip, then make your way out of the vault, (if you didn't fix the pump, expect a fight) go through Necropolis and get back to Vault 13.
  
• Make your way down to the bottom level of the Vault. Give the Chip to the Overseer (Chap at the start of the game) during the daytime.
  
• Congratulations! You have completed the first quest for Fallout 1.

Quick route
You can go directly to Necropolis, get the chip & back to the Vault. You don't need to level.
Takes only a few days.
1. Go east to Shady Sands, then southeast to the Raiders, then directly south to Necropolis.
2. Enter the first manhole. Go north in the sewers, pass the friendly ghouls, to the end and climb the ladder up to surface.
3. Head north to building with mutants. Tell the mutant (Harry) you are a ghoul and he will let you pass.
4. Go down sewer manhole to Vault 12, avoid the ghouls, take elevator to lvl 3, pass the ghouls to computer with the waterchip.
5. Grab the chip and head home (Watch out for the Ghouls!).
This allows you to get the waterchip immediately, at low level, without fighting anything!

This 'quick' guide was created by jjellison.home. Thanks!

Map
https://i.imgur.com/qFFETEm.jpg