You most likely crashed as a result of memory problems. This can happen when you are using a mid-tier PC to play on a server loaded with heavy mods, unoptimized scripts, or just as often a combination of both. DISCLAIMER: some players would argue that their PC is good enough and has plenty of RAM memory, like 6GB or more. So much that they don't expect to run out of memory. So here's the story - GTA SA is an old game from 2005, and you can run MTA with hardware from that era on most decent servers with ease. But servers that are not decent, but "bad" in the sense described earlier, are able to turn this old game into a more demanding one than modern titles. One that even hits limits of this 2005 game, which wasn't designed for what is being done. We mean that any usage on gta_sa.exe above 3.2GB, even if you have much more RAM memory available, will not be stable.
SOLUTIONS:
Find another server to play on
Upgrade your PC's hardware (most important is the amount of RAM memory) and perform some OS mainentance, limit the amount of processes using up memory.
If you're on a 32-bit OS, install a 64-bit version. For more information, please read https://forum.mtasa.com/topic/78081-32-bit-windows-crashing/
If being able to play on a certain server is really important to you, and you decide to upgrade, then please note that unless you get a gaming PC, depending on the severity things are "bad" on said server, it might only extend the duration you can play at once without crashing. If things are bad enough, you can crash within an hour from connecting while using the baddest gaming PC available. Example: a lot of russian total conversion servers. If you cannot upgrade your PC or improve your situation by one of the above steps, then unfortunately there's no option other than mind the (type of) servers you're playing on.