ASUS Rampage Extreme X48 Motherboard Review

Heat & Acoustical Testing

Finally...finally we have an MCH temperature sensor and an intriguing enough setup to do some testing on. This whole section essentially stems from a lot of forum reports that the Rampage Extreme runs the MCH a little on the hot side. Okay, so there are some reports that the temps of the north bridge are downright terrible. Then there are reports of guys removing the stock setup for water blocks and getting incredibly better results. We looked at the heat sink setup and it really doesn't look that bad. There is a copper plate sandwich sitting directly on the X48 IHS with a couple heat pipes in the middle going to the other heat sinks. The waterblock or heat pipe assembly then mounts to the top of the copper plate. In theory the setup should be great, but that isn't what the numbers were saying that people were getting, so, we did some testing based on others results. Let's first look at the various options we have that we used in testing.

Pulling the Fusion block off the assembly revealed a decent thermal paste application and a solid contact patch. So the patch is not exactly centered but still pretty good coverage over the hot middle part of the X48 chipset. The Fusion block itself isn't that bad a design either. It is clearly made of copper as holding it in your hand takes effort, and again, the thermal paste was fairly well spread out. Internals being unknown, we have no reason to believe that this block is a bad design. So far everything looks good in our opinions.

Moving on to the heat pipe attachment for air cooling, we mounted the unit with our Arctic Cooling MX-2 and ended up using MX-2 for all the mounts in favor of fairness. The heat pipe attachment itself isn't nearly as impressive as the Fusion block being completely made of aluminum and having only a single heat pipe. The base plate is pretty thin as well but with that said, it still should provide ample cooling for an X48 north bridge. The second photo shows the contact patch that we had after testing and removing the heat pipe. As we can see, there is near perfect contact between the copper plate and the heat pipe base. Again, no reason to believe the mount would be the reason for the high temps.

Getting the Fusion block up and running was a bit of a battle as the reducers needed to get our 1/2" loop down to the 1/4" or 10mm barbs on the Fusion block make for a worm clamp nightmare. At first we didn't tighten them enough and got leaks. Then we tightened them too much and the plastic tubes included to provide the male adapters something to connect to tore and leaked. Eventually we cut both tubes down and managed to get the setup working without leaks. Our one plea to ASUS is to come up with a better solution than 6 worm clamps, 2 adapters, and two 1.5" lengths of 10mm hard plastic tubing. There has to be a better solution to provide all loop sizes to mate to a block from the factory. Removable barbs with a standardized thread is the obvious choice so perhaps it is something ASUS should look into going forward.

The last photo above is our attempt to get the Swiftech MCW30 mounted directly to the X48 IHS...it failed and kept slipping off. The mounting tabs were just a hair short of reaching the wider X48 mounting holes. In the end, we had to settle with the testing the MCW30 on the stock heat pipe assembly secured with cable ties. Sorry, I won't be releasing photos of my jerry-rigged cable tie attachment but it was secure, provided an excellent contact patch, and had plenty of mounting pressure.

So we have our setups ready to go and we did our hour long testing with a ten minute idle period at the end. We then came across a forum post where the user had added washers to the mounting screws of the heat sink assembly and had impressive results. We figured, why not? So with a phillips head screwdriver in hand, we pulled the entire heat sink assembly, we saw the photo earlier of the naked X48 chipset. We then replaced the thermal material, again, with Arctic Cooling MX-2. We also added nylon washers to the base of the motherboard that are about the diameter of the original springs used by ASUS. This should have increased the mounting pressure of the entire assembly and was the idea behind the original user’s plans. Here is a close up of the additional washers we added:

This is when things got interesting and we received similar results to what the original forum poster had seen. Here is the chart of the four different setups that we tested, the results are quite obvious as to what was required for making the stock heat sink assembly shine.

The term "stock" in the chart refers to before we removed the heat sink/heat pipe assembly and re-mounted with the nylon washers. Like we said, it is an absolute no brainer as to what lowered temps almost a whole 10C on average under load with our overall overclocked settings of 477FSB and an increased vMCH voltage to 1.50v under load, just to add more heat to the testing. Idle temps lowered quite a bit and the drop off of the temperature from load was quite a bit steeper and far less gradual. So in the end, the stock heat pipe/heat sink assembly really isn't bad at all, heck, we would even go as far as saying it is pretty good. The only issue is that it appears that the assembly needs a little bit of help and added mounting pressure. Keep in mind, too much pressure and you will get into a warping issue with the PCB which we did encounter but we are willing to forgo that for much better MCH temperatures.