Install games on your D drive if you have one, but only if your C drive is running out of space

Your C drive is where Windows lives and where your system stores temporary files it needs to run fast. Your D drive (or any second drive) is extra storage space. Games work fine on either one, but installing them on D frees up room on C for the things Windows actually needs to keep your computer responsive. The catch: if your D drive is much slower than your C drive — which happens with older external drives or some budget setups — games may load noticeably slower, and you'll trade speed for space.

The real question isn't which drive is "better" in general. It's whether your C drive has breathing room. If you have 30% or more of your C drive free, install games there and stop thinking about it. If you're below 15% free, move games to D. Between 15% and 30%, it depends on what else you do: video editing or photo work means move them; light browsing and email means leave them.

Key Takeaways

  • Games run fine from either drive, but installing them on D frees up C drive space that Windows needs for temporary files and system performance.
  • If your C drive has less than 15% free space, moving games to D will noticeably improve your computer's speed and stability.
  • A game loads faster from your C drive than from a D drive if D is an older external drive or a slower second hard drive, but the difference is usually a few seconds.
  • You can move games after installing them without reinstalling them from scratch, though the process varies by game platform.

Why C drive space matters more than you think

Windows doesn't just sit on your C drive — it constantly writes temporary files there while you work. When you open a browser, edit a photo, or run a game, Windows creates cache files, swap files, and temporary data on C. If C is nearly full, Windows has nowhere to put these files, so it slows down. Your computer starts taking longer to open programs, games stutter, and even typing can lag.

This isn't about the game itself running slower. It's about your entire system choking because the drive where Windows operates is starved for space. A game installed on C that's 90% full will perform worse than the same game on D, even if D is slower, because Windows can't do its job properly.

How drive speed actually affects game performance

If your C drive is an SSD (solid state drive) and your D drive is also an SSD, the difference in load times is negligible — maybe one or two seconds. If C is an SSD and D is an older external hard drive, you might wait 10 to 15 seconds longer for a game to load. That's annoying but not a dealbreaker.

What matters more: whether your D drive is connected via USB 2.0 (very old), USB 3.0 (older), or USB 3.1 (newer). A game on a USB 2.0 external drive will load slowly. A game on a USB 3.1 external SSD will load almost as fast as your C drive. If you don't know which you have, check your drive's manual or the cable connector — USB 3.0 and 3.1 connectors are blue inside the port.

Moving games you've already installed

You don't have to uninstall and reinstall a game to move it. Steam, Epic Games Launcher, and most other platforms let you move installed games to a different drive through their settings. In Steam, right-click the game, select Properties, then Local Files, then Move Install Folder. In Epic Games Launcher, go to Settings, Installations, and add your D drive as a second installation location, then move the game there.

Console games are trickier. On PlayStation or Xbox, you can move games between internal and external storage through the system settings, but you can't choose exactly where. The system handles it automatically once you plug in an external drive.

When D drive speed becomes a real problem

Large modern games with lots of textures and detail load assets constantly, not just at startup. A game like Starfield or Baldur's Gate 3 pulls new textures and geometry from disk while you play. On a slow D drive, you might see textures pop in late, or the game might stutter when you turn a corner and new areas load. This is rare with modern SSDs but common with older external hard drives.

If you're playing competitive games where reaction time matters — shooters, fighting games, racing games — a slow D drive won't affect your input lag, but it might cause frame rate dips during loading. Single-player games with slower pacing are less sensitive to this.

The practical decision tree

Check how much free space you have on C. Right-click the C drive in File Explorer, select Properties, and look at the pie chart. If the blue (used space) takes up more than 85% of the circle, move games to D. If it's less than 70%, keep them on C. Between 70% and 85%, it depends on what else you store on C — if you have large video files or photo libraries there, move the games.

Next, check what kind of D drive you have. If it's a second internal hard drive or an external SSD, the speed difference is small enough that space savings win. If it's an old external USB hard drive, weigh whether you care about load times. A 10-second delay is annoying once; a sluggish computer all day is worse.

Frequently Asked Questions

Will games run slower if I install them on D instead of C?

Only if D is significantly slower than C, which usually means an older external drive. If both are SSDs or both are internal hard drives, the difference is minimal — a few seconds at most. If your C drive is nearly full, games will actually run better on D because Windows will have space to work.

Can I move a game after I've already installed it?

Yes. Steam, Epic Games Launcher, and most other platforms have a built-in move function in their settings. You don't lose your save files or progress. Console systems also let you move games between drives through system settings, though you can't pick the exact location.

What if I only have a C drive and no D drive?

Install games on C, but keep at least 20% of it free for Windows to operate. If you're running out of space, consider adding an external SSD — they're inexpensive and much faster than older external hard drives. Avoid filling your only drive past 90% full, or your computer will slow down noticeably.

Does it matter which drive I install Steam or Epic Games on?

The launcher itself should stay on C since you use it frequently and it's small. Games can go on either drive. Most launchers let you set a default installation location in settings, so you can tell it to put new games on D automatically.