Or, you can continue with your line of thought and ignore these fools that always advertise about how "U need 2 Upgrate!!!1!!"
Oftentimes, especially nowadays, it isn't completely your computer's fault as much as others make it out to be. Check your usage of your processing power for slow running speeds, you might find more worthless junk than you need running. That is often the biggest reason you get good rates on a old machine and crappy rates on a newer machine. The whole Linux thing isn't in your favor though, since the percentage of people who use it are lower, hence a lower chance of someone having a problem similar to yours. As such, if you get the solution through random luck, broadcast all the random crap you did here. Someone else can narrow it down later. Likewise, if you get the answer, repost it here. Sometimes search features work, and occasionally someone takes their head out of their rear when someone asks for something searchable and posts the link.
I do think a dedicated Linux forum is the best place to look though, since they are more likely to understand how things on that end operate and why there are issues.
Oh, and I don't get PTTG's joke either, and don't know a language besides English.
Seriously though, be sure you have the latest Linux version. I think it is
http://www.bay12games.com/dwarves/df_28_181_40d9_linux.tar.bz2There is no link for the Linux version on the main Dwarf Fortress page, so if you didn't dig through the dev log for the link, chances are you didn't get the one you needed.