Passive skills are lowered by 10 (%) when the difficulty is changed from Normal to Hard. SPECIAL stats (Strength, Perception, etc) modify skills with a considerable bonus. The game keeps track of this bonus throughout the game, in real time. Any changes to stats, (e.g. chem effects) during the game add to or subtract from this modifier. It is thus possible to reduce any combination of stats to zero, significantly lowering skill values.
It is possible to raise Small Guns, First Aid and Science to 127%, Repair to 118% and Outdoorsman to 115%, in the case of a player whose Perception, Intelligence and Agility are at 10 (possibly more if the player's stats are lower), Endurance is above three, with the listed skills at 91%. To lose Agility and/or Endurance, use Buffout or Monument Chunks, then wait. To lose intelligence, use Mentats and wait, or Psycho. To lose Perception, drink Beer, Booze, Rotgut, etc. If books are used from inventory (by left clicking and dragging) rather than from a weapon slot, time will not pass, and therefore stat effects will not wear off, until the inventory screen closes.[1]
| Name | Closest map marker | Location description |
|---|
| Big Book | Gecko Powerplant | On the shelves in the Supply Cabinet. |
| Big Book | Vault 8 | In a locker in the south-eastern quarters. |
| Big Book | Gecko | On the shelves in the Manager's Office. |
| Big Book | Stables | On the shelves in Myron's workroom. |
| Big Book | Sierra Army Depot | Two in the desk in the CO's quarters, level three. |
| Big Book | Sierra Army Depot | In the hands of a skeleton, level four. |
| Big Book | Navarro | On the shelves in the Commander's office. |
| Big Book | Navarro | In the workbench next to Quincy. |
| Big Book | Oil Rig | On the scientist in the mainframe room, Reactor Level. |
| Big Book | New California Republic (town) | On the bookshelf in the outpost, NCR Bazaar. |
| Big Book | Vault City | Merchant: Randall |
| Big Book | San Francisco | Merchant: Lao Chou, Flying Dragon 8 |
| Big Book | San Francisco | Merchant: Female merchant on Oil tanker |
| Cat's Paw | New Reno | Quest reward for Deliver ten Cat's Paw magazines to Miss Kitty |
| Dean's | Ghost Farm | On one of the skinless Slags. |
| Dean's | Gecko Junkyard | Inside the workshop storage room, in the stuff on the table |
| Dean's | Vault City | Downtown, inside Valerie's storeroom. |
| Dean's | New Reno | Salvatore's Bar, 1st floor, on the shelves in Mr. Salvatore's apartment. |
| Dean's | New Reno | New Reno Arms, inside the workshop in the back room (accessible from the street). |
| Dean's | Sierra Army Depot | In the desk in the CO's quarters, level three. |
| Dean's | Sierra Army Depot | In the robobrain assembly lab, level three. |
| Dean's | Mariposa Military Base | Two outside, one on the ground in the tent and the other inside a locker in another. |
| Dean's | New California Republic (town) | On the bookshelf in the outpost, NCR Bazaar. |
| Dean's | Navarro | In the middle workbench in the Vertibird hangar |
| Dean's | Oil Rig | Two on the shelves in the scientist's office, Detention level. |
| Dean's | Oil Rig | Two in CO's storage in the Barracks area. |
| Dean's | Oil Rig | On the scientist in the mainframe room, Reactor Level. |
| Hintbook | New Reno | From Father Tully in New Reno if you continue the game after destroying the Enclave's Oil Rig (if Father Tully is dead, you cannot get the hintbook) |
| First Aid | Modoc | On the bookshelf behind Grisham |
| First Aid | Mercenaries' Cave | In a locker inside their base |
| First Aid | Vault City | In a bookcase in the house near the Central Council building. |
| First Aid | Redding | On the shelves in Doc Johnson's clinic |
| First Aid | New Reno | On the shelves in Mr. Salvatore's apartment, Salvatore's Bar 1st Floor. |
| First Aid | Sierra Army Depot | In the locker in the infirmary, level one. |
| First Aid | Sierra Army Depot | In the desk in the CO's quarters, level three. |
| First Aid | New California Republic (town) | On the bookshelf in downtown clinic. |
| First Aid | Mariposa Military Base | Two in a rusty locker in the medical section on the second level. |
| First Aid | Navarro | In the workbench behind Quincy. |
| First Aid | Oil Rig | Two in CO's storage in the Barracks area. |
| First Aid | Oil Rig | In a locker inside the experimentation lab, Detention level. |
| First Aid | Oil Rig | Two on the shelves in the scientist's office, Detention level. |
| First Aid | Oil Rig | Three inside the Survival\Gear Locker inside the Trap Level. |
| Guns | Klamath | In a bookcase in the building near the Grazing Grounds. |
| Guns | Toxic Caves | Desk inside the storage bunker. |
| Guns | Den | In a bookcase inside Lara's gang hideout. |
| Guns | Ghost Farm | On one of the skinless Slags. |
| Guns | Vault City | In a bookcase inside Cassidy's room in his bar. |
| Guns | Vault City | Inside a desk next to Stark. |
| Guns | New Reno Shark Club 1st floor | On the shelves in the room with the bald thug. |
| Guns | New Reno Arms | On the collapsed shelves in Eldridge's quarters (you need to kill the dog to get to it). |
| Guns | Mercenaries' Cave | In the safe. |
| Guns | Redding | In Ascorti's office, in the casino. |
| Guns | Sierra Army Depot | In the locker in the barracks, level one. |
| Guns | Navarro | On the shelves in the Commander's office |
| Guns | Navarro | In the middle locker in the Vertibird hangar |
| Guns | Oil Rig | In the desk at the security checkpoint, Detention level |
| Guns | Oil Rig | In the desk in the storage room, Barracks level |
| Scout | Klamath | On one of the kids in the Traper Town |
| Scout | Vault 8 | In a locker on the living quarters level. |
| Scout | Redding | In the middle room in Malamute Saloon |
| Scout | Redding | On the shelves next to Marge LeBarge |
| Scout | Redding | On the shelves in the ruined building at the Great Wanamingo Mine |
| Scout | New Reno | On the shelves in Mr. Salvatore's apartment. |
| Scout | Oil Rig | Two in CO's storage in the Barracks area |
| Scout | Oil Rig | Three inside the Survival\Gear Locker inside the Trap Level |
