So, Robert -
Where we at on this?
The simplest thing to do would be to get that rear case fan blowing out. I can't say that every fan is built this way, but I've looked at a few dozen and they all blow towards the the four little plastic arms that suspend the motor hub. Although it'd be nice to verify by finding the little arrows molded into the frame, you can generally tell at a glance if the fan is spinning the intended direction by determining if the air is moving from the open side of the fan towards the side that suspends the motor hub. That would be the side with the decal. If the fan is attached backwards, turning it around should be easy.
I can tell you from my own experience with a brand new 120mm fan, don't try to handle the fan while it's running and bonk it up against something and break off a blade
This suggestion needs to be done ASAP, then check your temps with this program:
SensorView Pro (Free to try for like 21 days – Is excellent)
http://www.stvsoft.com/download.php?id=122
The second hardest thing to do would be reversing the PSU fan. Remember I mentioned old ATX PSU's that blow in? I had one of those. I opened up the PSU, removed the fan screws, and flipped it over. Simple fix. The PSU should be allowed to set overnite unplugged from the wall before you open it up because it has some fat capacitors inside that can give you a nasty shock. I've heard some say that you can discharge them by unplugging the PSU from wall and holding the PC's power button down for a few seconds but I'm not sure that's accurate.
I am not sure you should go there. This might just upset the apple cart and quite possibly lead to more heating. I do think you should consider adding a front fan if the above step does not solve some of your issues.
The third hardest, but quite possibly most valuable in terms of your own learning experience and your CPU's happiness, would be to get some good quality thermal paste and tune up that interface between the CPU and the heatsink. Most PC owners will never go there, but it's not rocket science. Lots of pictures and diagrams on the web. Some heatsinks come off really easy, others are a cast-iron SOB. I hate the OEM Pentium 4 heatsinks with those plastic half-twist screwlock thingies. It would be great if you can borrow a friend who's got any experience with this to take a look inside. And you only need a tiny dab of paste so if he's got some Arctic Silver you could borrow..
This will probably make the most difference if your temp problems are not solved by the fan changes/addition. Just make sure before you change it that the heatsink fan is blowing down, because if someone put in on backwards (pulling air up is backwards), then that can cause about t10c difference. I also agree about the Artic Silver. That can make several degrees difference. Here is a link that explains how to do this:
http://www.arcticsilver.com/arctic_silver_instructions.htm
I am sure that both Bartender and I would either or both tell you that too much paste is as bad as not enough. Therefore, read the directions for applciation very carefully, and clean the old off as per the instructions before you reappy any.
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