Recently, I build a new computer. I decided to take the opportunity to upgrade from Windows XP Pro x86 SP2 to Windows 7 Ultimate x64. My FNV game under XP had 192 mods (as tallied by the Load Order Sorting Tool (LOST)) and was 100% stable. My computer was old, but I took pains to ensure that everything was compatible, and if it wasn't I either fixed it in FNV or the GECK.

I backed up my mods and data, put together the new x64 system, and re-installed FNV. Restored my mods / load order, and I crashed just prior to the main menu (after the Bethesda marketing screen). Puzzled, I tore my load order apart to see what was offending.

I found that rather than a single mod causing the crash, it was the raw number of them limiting me. 165 was the limit. At 165 I crashed before the main menu, but at 164 I was fine. If I removed 28 mods, any 28 as long as I wasn't removing something with a dependency, my game would start and play fine. I tested this several times, to make sure I wasn't removing a certain set of 'crash prone' mods, and it had no affect. The raw number was causing me to crash.

So I'm wondering: anyone else using a 64 bit environment that has hit this limit? I'm wondering if some 32 bit compatibility is limiting our number of mods, and if this could be patched similar to how NVSE / stutter remover / 4 GB enabler work. I think the theoretical limit is 255, or 2^8, implying there is an 8-bit integer assigned to storing and processing mods. I don't know enough about programming to even make a guess, but does someone more knowledgeable than me know why a 32 bit program running in a 64 bit environment would lower such a limit? It's confusing, but seems like something the community could fix.

I can't explain your problem, but I can confirm it's an 8-bit integer for mod numbering. The base game takes up number 0 for FormIDs (the last 24-bits identify the specific FormID, the first 8-bits is the index number), number 255 is used for temporary (or something?) objects, and then mods (including DLCs) use the numebrs from 1 to 254.

Queue

Isn't that why there's a program that turns multiple .esp files into one .esp file? I mean, if there's something like 15 mods that each do something completely different, with no overlap, making them be one mod should be nothing but beneficial.

I have heard of people having this problem before. http://www.newvegasnexus.com/downloads/file.php?id=35003 can help you get around your problem with a bashed patch. It's not as hard to do as people think it is.

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