Just an update on the current situation.......... It looks like trying to compare i386 to AMD64 on this particular system is a moot point at this stage as I cannot get the NVidia closed src driver to work and the open src driver is __not__ satisfactory for 3D work. It being quite slow and not doing the textures correctly. The problem with the closed src driver is it causes the xserver to exit just after start up due to a memory violation apparently in the pthread library. This happens on all software configurations i have tried, Four different kernels, two versions of Debian (7.2 and current Sid) and 3 differnt versions of the closed src driver. I have posted a bug report onan Nvdia developers forum, there has been no reply as yet. Nvidia docs do say there is somekind of known issue with the pthread library causing crash's so I _MAY_ be suffeering from this. I will have a think about this today, what I may do is to swap the video card. I have a Radeon 2 gigabyte HD7870 spare currently and there are good reports on the latest driver 3.11 beta and this is avaible for Sid. This will save having to reinstall debian. Hmmmmmmmmmmmmmm I may swap the GTX680 into a ASUS X58 MB, this being an older known reliable gamming MB, as the 680 should be OK no reports of problems can be found on the net. Is'nt it a pain when hardware gives problems........... Lindsay