That being said, if you're still interested in downloading a compressed version of Call of Duty: Black Ops 1, here are a few things to keep in mind:

Downloading "highly compressed" games from third-party or unverified sites is risky. Call of Duty: Black Ops Minimum System Requirements

Delete the players folder inside the game directory. The game will regenerate it with default settings.

He opened it. Inside were files he’d deleted years ago: school essays, old photos of his dog, a recording of his grandmother’s voicemail. But also new files. Videos. Timestamps from ten minutes in the future. He clicked one.

A radio crackled. A voice—distorted, layered, like three people speaking at once—whispered: “The numbers, Mason. What do they mean? But this time… the numbers are real.”

Most modern PCs can easily run the game, as it only requires 2GB of RAM and a 256MB video card. Activision Support Safer Alternatives for Reduced Sizes