Since you have specified the Asus A7V333, which has overheat protection based on the AXP internal diode, if you have heat problems the system will simply shut down.
If you assemble the system correctly and properly install an adequate HSF - the retail version does just fine for most installations - your system will run just fine and you won't even need to worry about it shutting down.
If the thought I thought I thought had been the thought I thought, I wouldn't have thought so much.