Many ROM sites throttle your download speed unless you pay for a "premium" account. Since the megathread often uses the Internet Archive, you get the best speeds your connection can handle.
The Ultimate Guide to the R/Roms Megathread: Your One-Stop Digital Archive
If you’ve ever dipped your toes into the world of emulation, you know the struggle. You spend hours setting up RetroArch or PCSX2, only to find that the "safe" site you used ten years ago is now a minefield of pop-ups and malware.
Within those tabs, you’ll find links to various Archive.org collections.
If you find a broken link, report it on the subreddit. The megathread stays alive because the community maintains it.
The megathread is typically pinned at the top of the r/roms subreddit . Look for the "Megathread" flair or the "Pinned Post."
Click on the tab for the console generation you’re looking for (e.g., "Sony," "Nintendo," or "Retro").
Most emulators won't run without a BIOS (the console's internal operating system). The megathread provides these essential files, which are often the hardest pieces of the puzzle to find. How to Use the Megathread