Textures never end loading (hours) and lag is abnormally high (varies from sim).
Network load is also insanely high.
Tested with all graphics set up at minimum on following hardware:
Mac OS X 10.5.4
Core 2 Duo 2.4Ghz
4Gb RAM
GeForce 8500GT 512Mb
MacBook
Mac OS X 10.5.4
Core 2 Duo 2.1Ghz
1Gb RAM
Intel X3100
However this did not happened with 1.19 nor 1.20, and does not happens with 1.21 on same hardware with other operating systems (Tested with custom graphics all at maximum):
Lenovo X300
Windows XP Professional
Celeron D 2.2Ghz
1Gb RAM
Intel X3100
Gentoo Linux amd64
Intel(R) Pentium(R) Dual CPU E2140 @ 1.60GHz
1Gb RAM
nVidia Corporation GeForce 8400 GS 128Mb
Re the Textures never end loading, please see the main issue VWR-8503. Please add you full computer environment Help > About Second Life, comments and vote to that issue.
Re the Mac OS do you see the same issues if you update to 10.5.5 http://support.apple.com/kb/HT2405
In the release notes for Viewer 1.21.6 there are some workarounds for issues with Macs with an 8600M graphics card http://wiki.secondlife.com/wiki/Release_Notes/Second_Life_Release/1.21#Known_Issues_in_version_1.21:
VWR-7779[c]: Mac viewer suffers from cyclic pauses/freezes/fatal hangsThe suggestions might help with your Mac computers, although you have different graphics cards.
There are also some suggestions here Turn off WindLight rendering http://wiki.secondlife.com/wiki/Turn_off_WindLight_rendering
Please check Edit > Preferences > Graphics > Under Hardware Options please set Texture memory no more than half your graphics memory.
Please see this article for information on Fast Timers results http://wiki.secondlife.com/wiki/Debug_Help
For account-specific help please post a Ticket with Support http://secondlife.com/support/
Thank you : )