Advice on Finding and Organizing ROM Sets for MAME

Hello there,

I am new to the retro gaming scene and have recently started exploring emulation. I have set up MAME on my PC and managed to get a few games running; but I am quickly realizing that managing ROM sets can be quite overwhelming; especially for someone who is just getting started.

I have been reading about the differences between merged; split; and non merged sets; and while I think I understand the basic concepts; I am struggling to decide which option would be best for me. My primary goal is to keep things simple and organized while ensuring compatibility with MAME. Could anyone share their experiences or advice on how to choose and manage ROM sets effectively?

Additionally; I have come across a few websites offering ROMs; but I am not sure how reliable or safe they are. I know RetroRoms has a great reputation; and I would like to hear more about the best practices for downloading ROMs from here or other trusted sources. Are there specific tools or utilities you would recommend for verifying and organizing the files? I have heard of tools like ClrMAME Pro but have not tried it yet.

Lastly; I am curious if there are any legal considerations I should keep in mind while collecting ROMs. I want to make sure I am staying within the bounds of what is allowed.

Also, I have gone through this post; https://www.retroroms.info/forum/topic/Needing-a-MAME-Set-and-not-uipath-which-file-to-DL.htm which definitely helped me out a lot.

I am excited to dive deeper into this hobby and learn from the expertise of this community.

Thank you in advance for your help and assistance.

Some roms share assets. Like when there is version 1 and 1B of a game the file containing the sprites can be shared.

Merged means you put all parent rom related roms into a single zip. Non-merged will duplicate every asset for the child roms, so you end up having a lot of duplicate parts inside multiple zips. Split is basically merged, but the main game file is put into a separate zip, so you can better index your games for some frontends for example.

Non-merged will probably give you best performance and you can easily remove games and not worry about any rom needing any other rom to work.

Merged is best space saver.

Split is a good tradeoff.

What you want to use is your decision, personally I usually use merged for my database and split for usage.

Maybe you want to look for something called "roms megathread". :)

For managing roms, you basically need the data files and some "index" to verify them and build the current romset. (aka dats)

You can then use ClrMAME Pro to build the current romset. The internal file structure of a romset will change basically with every new emulator release and you need to at least fix, if not rebuild the set for every new release. Besides Mame there are the No-Intro dats and other sources like Redump. The No-Intro database is basically the current state of the collection and does not need to be rebuild if you want to use them as is, which is a mayor difference to Mame or FBNeo romsets, which need to fit the current version perfectly to work.