I have not run into this problem; our systems are fairly similar, though you have a better graphics card and I kept my sight range comparable to the displayed area on-screen. I have a Duron 1300 (it played fine on a Duron 900 as well), 512MB RAM, Win 98SE, GeForce2 MX, Audigy sound card, Asus A7V-E MB (VIA KT133).

If you want to check if your site range is to blame, get a crappy ring/amulet and give it a large negative sight bonus with the item editor;

http://hem.passagen.se/spove

See [i]please help with my blind hero[/i] for a description and details.