Giving Intel Core 2 Duo A New Appearance
If you've maxed out your processor by overclocking and want to squeeze more out of it or are just looking to reduce core temperatures lapping the processor might be something worth looking into. All Intel LGA775 processors use the FC-LGA4 package, which means that the processor die is on top of the substrate on the opposite side from the LAND contacts. This package consists of a processor core mounted on a substrate land-carrier. An integrated Heat Spreader (IHS) is attached to the package substrate and core and serves as the mating surface for the processor component thermal solution such as a heat sink. Intel actually solders the IHS to the core of the processor, so the contact on the processor is usually not of concern. This brings us to the situation on hand. Many of the Allendale and Conroe processors that we have lapped have had heat spreaders that were not flat.
We went up to the local automotive supply store and picked up a number of different sandpaper packs ranging from 400 grit to 2500 grit. Using 2000 grit to 2500 grit sandpaper is far better than the factory finish, but for those that want to go crazy can invest in 1 micron diamond lapping compound to rub out all the sanding marks for a true mirror finish.
We took out Intel Core 2 Duo E6700 processor and started out lapping the IHS on a counter with 400 grit sand paper. After about 10 passes on the sandpaper it was obvious that the edges of the IHS were higher than the center, which means the hot core is not coming in direct contact with the base of our already lapped water cooling block.
After a few minutes of 400 grit sanding we started to see copper that was previously hidden by the nickel plating that we have started to sand off. All Intel LGA775 processors feature copper integrated heat spreaders, so getting one of the flat will allow for great thermal transfer between the IHS and our copper water block. Once the block was flat and all the nickel was gone we moved on to finer sandpaper grits and called the surface of the IHS done after we used some 2500 grit paper on it.
The final result of lapping the processor was amazing. For less than twenty minutes worth of work we were able to take our Intel Core 2 Duo processor from having an uneven IHS to having a perfectly flat top hat. We took our lapped Intel Core 2 Duo E6700 Processor and ran it in the ABIT AW9D-MAX motherboard and found that the lapping reduced the idle temperatures by 2-3 degrees Celsius. Before the lapping it would idle 34-35C and after we were seeing 31-32C. Before we took load temperatures we thought we'd keep going and removed the IHS all together.
Trying to Remove the IHS Safely
While we should have been happy with lapping the IHS we went one step further and removed the IHS. This is not something we suggest that anyone should try and in fact there is only a one in four chance that it works. Even if the processor works after IHS removal the load plate has to be removed from the socket as the core of the processor will sit below the load plate when it's locked down on the CPU.
We started out by running a razor blade under the IHS cutting the adhesive material that attaches the IHS to the processor. After we ran the razor blade all the way around the processor we found that the IHS won't budge as it's soldered to the core as we previously mentioned.
To get the heat spreader off we used four razor blades and placed two under opposite corners to apply force on the IHS. We then got out the Sears Craftsman propane torch and fired it up.
We then lightly heated the IHS with the torch for a few seconds at a time. The torch was never left in direct contact with the IHS for more than a second at a time. After three or four passes of the torch on the IHS a loud pop happened and the IHS went flying off the die.
After the dust settled this is what the scene looked like. The IHS was off the processor and the CPU looked like it had seen better days. The processor was cleaned with Isopropyl Alcohol 91% and the extra solder on the core was scraped off using a plastic credit card.
After the CPU was cleaned we used four layers of electrical tape on each side of the core to prevent cracking the die and removed the load plate off our abit AW9D-MAX motherboard so the water block would make contact with the core and not the load plate. We applied Arctic Silver Lumiere to the core and after a test fitting to make sure the water block made contact with the die we fired up the test system. The system would power on, but sadly it wouldn't post. It seems our Intel Core 2 Duo E6700 Processor didn't like the surgery we performed on it, but hey that's the price we expected to pay before we started to remove the IHS.
Legit Bottom Line: Lapping the IHS on all Intel LGA775 processors will improve thermal temperatures and we found out the hard way that removing the IHS is a really quick way to destroy a good processor.