Extreme Overclocking the Pentium 2.4C

Street Price: N/A
Date Reviewed: July 3, 2003
Article By: Joey Chao

Dry Ice Setup and Results:

Dry ice cooling is a very unconventional way to cool a CPU. The idea is that dry ice gets very cold, around -78C, obviously much colder than our Prometeia. You have to have a container to mount on the CPU. The dry ice will go inside of the container and some liquid (that won't freeze) will have to be added to give more surface area to help keep the container cool, which in turn cools the CPU. There are a number of issues that come with dry ice cooling. Condensation is probably the biggest factor and remains to be the reason dry ice is not something that can be used all the time. There is no way to keep the condensation in check and the possibility of something shorting out and dying is high. The dry ice is just too cold to even really think about condensation proofing the socket, motherboard, container, etc. The other major factor is that dry ice will constantly be evaporating since it has such a low boiling point. You will have to keep adding more ice while the system is powered on.

Here is the container that will be mounted on our CPU. You can use a program to design you own block and then have it machined somewhere local. We are currently designing one for our Radeon 9800 Pro.

Here is what our test system looked like after the block was mounted. Notice that in this picture we did not insulate the block. We did later insulate it with foam to try to help reduce the rate at which the dry ice was evaporating.

After everything was installed, we went to the local grocery store and purchased a pound of dry ice for $0.80. The dry ice was smashed into very small pieces so that it would make more contact with the container and liquid. The liquid that was eventually used was rubbing alcohol just because it was the only thing that was laying around at the time. As soon as the liquid was poured in, the dry ice began boiling. Liquid was spurting out the sides of the container onto the system components, but lucky for us the system was not on yet until the mix settled down. The temperatures reported in the BIOS were not accurate at all. It's because the CPU was too cold and the diode doesn't read that low. Since were are racing against the clock (limited supply of dry ice), we just wanted to see what the highest overclock we could get was. So how fast did it go?

4GHz with a 2.4C is amazing. This is a 1.6GHz overclock and puts the FSB at 334! This is an incredible speed and it was running fine. We tried to run some benchmarks but the AGP/PCI issues got us one more time. Because of the extreme FSB, we lost a hard drive because the PCI bus was out of specification. This is disappointing because the scores would have been very nice, especially the memory bandwidth. Even though our board got flaky at super high FSB's, not many people will ever overclock that high because of the issues involved and the fact that this system can not be run 24/7 or even a couple of hours. So in short, the IC7-G is a very very good overclocker.