Eagle Lander 3D (EL3D) is happiest in a machine with a high quality 3D graphics card. In the past PCs were only judged by their cpu/processor speed: a 3.0ghz machine was faster and more powerful then a 1ghz machine. For 3D applications this is not true!
A 600mhz 'old-clunker' PC will fly EL3D much smoother and faster then a 3.0ghz screamer if the 'old-clunker' has a better graphics card. The 3.0ghz PC will will churn out Excel spreadsheets and access databases five times faster then the 600mhz machine - but those are office applications - not 3D applications.
Modern PC manufacturers do not by default put high quality graphics cards into their mainstream computers because they know that most people just use their PCs for email, internet, spreadsheets, etc.. As I write this, the Nvidia FX 5200 graphics card is the most commonly installed graphics card on new computers for the home and office. The 5200 card is fine for office applications and can run 3D applications too. Nevertheless, the 5200 is only about 2/3rds as fast as my old GForce3 3D graphics card from nearly 4 years ago! The reason: cost. A 5200 card costs the manufacture (and you) under $50. A top quality card such as the Nvidia 6800 or ATI X800 costs nearly $500 - and - the difference in performance is about the same as the cost differential - 10x.
With the above in mind, the basic requirements for EL3D are:
1ghz computer with at least 256mb of memory.
3D graphics card with at least 128mb of memory.
Windows XP (preferred), Windows 98, Windows ME, Windows 2000
If you can live with lower frame rates, computers with less capabilities will still run EL3D. Laptops can be especially marginal. The graphics adapters in most laptops are usually barely 3D capable, however laptop manufactures are starting to respond with better video cards. As I write this, the best graphics adapters installed in top rated laptops include the Nvidia GeForce FX Go5700 and ATI Mobility Radeon 9700. They are both pretty good - but still not top of the line compared to desktops.
A personal opinion: I have always purchased PCs with the best graphics card available at the time. It adds more to the cost of the computer but I feel it is worth it. Also, to extend the life of my computer I will usually upgrade to a new graphics card at least once in it's lifetime. It is easy to do - just buy the card - open the box - pull out the old one - stick in the new one - close the box - boot up the machine - install the graphic drivers. The whole operation takes 15 minutes - and - you can use your old card for fishing lure construction.