Some of you already know that I recently bought a dual 867 MDD.  When I first got it the temps were really high on the cpu board (around 58c)  The tower was pretty dusty inside so I gave everything a good blow with a can of air and also cleaned the 120mm system fan blades.  doing this along with using some new thermal paste brought the cpu board down to 55-56c.  I wanted below 50!@#

Today, after spending 13 bucks at my local computer shop on a HD cooler fan (80x80x15 fan), an 80mm fan to mount on the back and suck hot air out and a tube of much better thermal paste.  the stuff I used before was 25% silver and the new stuff is 99%.  the MDD is already so loud that I can't even hear the 2 new fans.  I put the hard drive fan right in front of the HD by the heatsink and turned the fan around to blow at the heatsink instead of the HD.

Temp on the cpu board now....  49.4c and stable there!@#  not bad for 13 bucks and a very small amount of effort.  most of all when you consider this thing ran as high as 59c when I first got it.

I am currently waiting for a pci slot fan I bought on ebay to arrive also.  I hope that will get me down to the mid 40's!!!

here are some pics:   

right now its running at 46.9c

plus the ocz silver thermal paste (re-branded arctic silver) I used is said to work even better after 100-200 uptime hours.  I guess it just bonds better after a week of use..

my temps keep getting slightly lower.  i'd say about .1 lower every couple hours.  many claim to get an 8-12c drop after a full week.  I tried booting without the 2 new fans on just to see how well my paste was working so far and my temp was about 52.3.  so down about 4 from paste alone.  plus since many say they get at least an 8c drop in total once its properly bonded I may have another 4c+ drop to look forward to.  its amazing what simply using quality paste can do. 

the hard drive fan blows 32 CFM of air directly on the heatsink at 3200rpm so that helps a lot also.  the fan on the back is only a 2000rpm and blows 22 CFM but the air it blows out feels quite warm so its doing its job.  both are very quiet.

this is just more proof of how just a bit of cash and some good old fashioned resourcefulness can get a lot done.

looking good!!!

I would HIGHLY suggest selling the CPU from it and buying a different model. I have four dual 867MHz MDDs where i work and all of them have crapped out. (though I did get to buy 2 quad G5s and now 2 3GHz Mac Pros to replace them!) I had a dual 867Mhz for personal use and the processor burned up (yes, BURNED. the white seal around the right processor was turned brown and the top was melted.) I have since put a Dual 1GHz cpu in there and it runs much cooler anyway. I also put a small fan right below the DVD drive, it seems to keep the side of the heat sink that the 120mm fan doesn't cool. The system runs at a Maximum temp of 115°f. Anyway, just a word of caution.

most people that keep the dual 867 nice and cool have great experience with it.  some say that 58c/135f is normal for all the dual MDD but its not healthy.  shame on apple for putting them out there like that when they could have easily made it run much cooler like I have.  besides..  my dual 867 is a later model that used underclocked 1ghz chips.

I honestly notice the system having less lag and in general it seems more precise now.

from the research I have done the pci exhaust fan i'm getting soon from ebay will lower the temps by a minimum of 8-9c.  so when all is said and done the cpu board on my mdd will be around 40c/105f.  thats cooler than single G4's

many people have dual 867 mdd..  they were by far the best selling mdd of all the speeds.  it sold so well that they continued to make the dual 867 when the rest of its series was discontinued.  ie when the fw 800 models came out.  you are the first person I have ever heard of having a bad experience with them.

44.3c now!@#

this is amazing!  plus I still have a pci slot exhaust fan to install.  below 40 here I come!!!

its really not that loud.  I got the pci slot fan today and even with that running also it doesn't seem loud. 

I like the roar of computers anyway.  a true geek would never have a silent computer  :P

I agree with that