They Won't Run Without a HeatSink

Just a few days ago I upgraded my Pentium II 450 to a Pentium III 600 by simply swapping out the CPUs. Before attempting the upgrade, I made sure that my motherboard could handle this processor. The Pentium III 600 is the fastest CPU that is compatible with my Intel SE440BX-2 motherboard. I found out (the easy way, luckily) that the Pentium III processors cannot be run without a heatsink. Heh.

Here's the deal. I bought an OEM Pentium III 600 from AccessMicro.com while ignorant to the fact that the OEM version is not supplied with a heatsink. When I received the CPU... and nothing but the CPU, I figured that I would simply swap my current Pentium II heatsink and stick it on the Pentium III. Little did I know that they changed the design of the CPU casing and heatsink attachment. The Pentium II heatsink does not fit on a Pentium III processor. Concurrently, the motherboard retention mechanism is also different from that provided for the Pentium II.

Now I had two CPUs… one with a heatsink, one without. I decided to plug the Pentium III into my motherboard without a heatsink just to see if it would work. I was planning to go through boot up just to verify that the processor would work with my motherboard. I removed the Pentium II and installed the heatsinkless Pentium III. I turned on my computer and it froze after displaying my graphics adapter information. I tried rebooting a bunch of times and pretty much got the same thing. One time it displayed half of the Micron logo that appears during boot up. Hmmm… Was the CPU dead?

The next day I borrowed a Pentium III 550 chip (with a heatsink) from work and brought it home. I plugged it into my motherboard and it worked perfectly! Hmmm… was my motherboard only compatible with a Pentium III 550 or below? Maybe I could swap chips… keep working Pentium III 550 for home and leave the Pentium III 600 at work. Regardless, I needed to buy a heatsink because one of the CPUs would be heatsinkless.

On my way home from work the next day I stopped by CompUSA and picked up a dual fan Pentium III heatsink. Yeah, I paid more for it than I would have if I had ordered it from www.3dcool.com or www.frozencpu.com, but I wanted it then and there… I didn't want to wait for shipping. When I got home, I figured I'd try the Pentium III 600 one last time in my computer. I easily attached my new powered heatsink and plugged that baby in. I turned on the power and the dual fans started humming. The computer flew through boot up and into Windows! Woah!

Maybe I'm just a CPU newbie, but I didn't realize that CPUs would shut down if they detected minimal or no heat dissipation. I figured that a CPU could run for at least a few minutes without a heatsink… but I was wrong. I guess the CPU can determine whether or not heat is being removed, and it will automatically halt if it determines that it is on a path towards destruction. Pretty cool… no pun intended.

Since this installation, the CPU has been working flawlessly. Not problems whatsoever. I didn't destroy it by powering up without a heatsink. Also, I had to remove the old Pentium II retention mechanism in order to fit the Pentium III 600 to my motherboard, so the think is being held in there by the slot alone… and there have been no problems. That reminds though, I need to order a Universal Retention Mechanism.

Overall, I have noticed a pretty good increase in performance! My Creative Labs GeForce graphics card was being held back by my old CPU, and now games like Unreal Tournament and HalfLife:Counterstrike scream at full res, full details. You can pick up a Pentium III 600 Retail chip for about $120 - $160 now… and it's the biggest jump that you can make with many older Pentium II 450 machines. Highly recommended… but only with a heatsink. :)