90c is where solder gets brittle and graphics cards get broken..
.. so try and stay below 80 if you can.
Cleaning up the cables is a good start, if you don't have dedicated cable storage areas use cable ties.
Make sure you have a fan blowing in at the front and one blowing out at the back to pass air through the case.
nVidia's are not very good for mining with, if you have a friend with a decent Ati card see if they will swap
https://en.bitcoin.it/wiki/Mining_hardware_comparisonMy case has 4 fans in it, and I am working on getting a better setup (getting some Xilinx fpgas)
just redid the wiring a bit, lets see if that works xD