We are having a strange issue with line display. These are new computers, Windows 7, 64 bit, ATI FirePro V3750 card. I've installed Civil 3D '09 & '10 and Land Desktop '09. When you zoom in real close on linework, the lines don't display where they really are. If you try to pick them or snap to them, they're not where they appear to be on the screen. If you select them before you zoom in, wysiwyg. the problem occurs in both Land Desktop & Civil 3D 2009 but NOT in 2010. Our old 32 bit XP systems don't have the problem on '09 or '10. I tried putting an old 32 bit XP image on one of the new computers & don't have the problem. So I'm thinking I've narrowed it down to the 64 bit '09 deployments of C3D/LDT but I'm not sure where to go with it from here. Any ideas?