Get more fans, reduce occupied space, tie wires back, increase air flow, and update heat paste.
Clean all dust out of all heatsinks and fans and off of any memory or any exposed chips.
Contrary to the past few years of opinions that say using some modified heat paste, and how it reduces temps by a drastic amount. I am currently using original heatsink that came with my CPU, and it has the factory tape on it. I have owned it for about 3 months now and done some pretty stiff gaming, mostly Crysis (demo) and Need For Speed Carbon and most wanted. My temperatures are amazing, but as I know with all things, it wont last. Or maybe it will. My current temperatures are as follows:
<taken from everest>
Temperatures
Motherboard 28 °C (82 °F)
CPU 22 °C (72 °F)
HDT722516DLAT80 31 °C (88 °F)
MAXTOR 6L080L4 23 °C (73 °F)
Cooling Fans
CPU 3013 RPM
Chassis 4116 RPM
Yes I know the Hittatchi is a little warmer than it could be, but in all the time I have messed with computers, I have never seen under 90 degrees for the CPU , other than right at boot. and that was typically around 89 degrees. I will be buying more of the heat tape that came with my Sempron if I can locate it.
Many people suggest that you use some paste/metal mix stuff. I have never been to keen on that junk, after it warms up for a long time and gets used a few times the stuff tends to harden, or become so tacky it’s like jb weld and could damage a few things when removing parts when cold.. Plus temps where always at least 8 degrees warmer than if I used the $3 white packets of paste. the major issue with the white stuff, well, you have to tend to it often and redo it atleast once every three months.
I try and not block any path of airflow. i have double checked airflow with a piece of scotch tape to see how it flaps and where it flaps.
The best cooling for a case involves a dremel, a drill, a metal file, 80 mm fan. and a brave brave soul. you use the dremel and a drill to punch an 80 mm hole at the top of the case facing upward and build yourself a fan there blowing air inward. the reason for inward is so you do not steal the air from the power supply cooling, that would easily increase the temp of ps unless you either make a tunnel or a blockade but would drop overall temp of case, now a tunnel makes great for making sure you blow air directly onto and across the motherboard.
Another suggestion is three 50mm fans across one of the CD-ROM bays but you have to build a frame for them.. which I will put on the site later… oh… and it is frickin’ loud.