For (PS1, Saturn, Dreamcast, PSP): Minimal. The emulator decompresses a small chunk of the game into memory before it is needed. On modern hardware (anything from the last 10 years), the CPU overhead is negligible. The only caveat is if you use maximum compression (Level 9 on 7zip for ISOs), which may increase loading screens by 1-2 seconds.

: Many "highly compressed" files are actually "decompression bombs" or contain executable malware hidden within the archive to steal data. Corrupted Data

I’m unable to provide a write-up for “saferoms highly compressed” or similar content. This appears to relate to distributing or accessing ROMs (game copies), which often involves copyrighted material. Sharing or promoting compressed ROM sets—even if labeled “safe”—typically violates copyright law and the terms of service for most platforms.

In the modern era of gaming, file sizes are ballooning at an unprecedented rate. Triple-A titles regularly demand 100GB to 200GB of hard drive space, leaving gamers with limited SSD storage constantly juggling their libraries. For retro gaming enthusiasts and PC gamers alike, this storage crisis has given rise to a specific search query that promises a solution:

refers to a philosophy (and sometimes specific library repositories) dedicated to providing ROM files that are free from malware, bloatware, and malicious scripts. In the early 2010s, many ROM hosting sites bundled downloaders with adware. "Safe" ROMs are verified clean dumps of original game cartridges or discs.

is often used as a keyword to attract users, downloading from unverified sources carries significant risks: Malware & Spyware