ASUS Rampage Extreme X48 Motherboard Review

Stability & Overclocking

It is finally time to get down to business and see what this motherboard can make this hardware do. We will not just focus on stable FSB overclocks but also on memory stability in testing. The XMP profiles of a couple kits will be tested for full stability. We will actually start there so let's see if our 2x1GB XMP Corsair Dominator kit has any issues at its XMP defaults of DDR3-1900 7-7-7 1T.

2x1GB XMP Memory Stability Testing

So far so good with the first kit of memory. There wasn't so much as a hiccup from first boot with this kit. They went straight into their XMP settings and ran right through the stability testing from first boot. Next up is our G.Skill PI 2x2GB PC3-16000 kit.

2x2GB XMP Memory Stability Testing

We had to go into Vista x64 for this testing and once again, not so much as a groan of discomfort from the system. It handled the G.Skill PIs XMP profile like a champ and churned through stability testing. vDIMM was set bang on to what the kit calls for and the kit ran like they should. Unfortunately, this is where the memory clocking went from perfect to a bit of a battle, more on that after the next screenshot.

Maximum Memory Stability Overclocking

Things got difficult when we tried clocking our 2x1GB of G.Skill gem PC3-12800s that have previously run dual 32M SPi at 1100MHz 8-7-6 on the 790i platform. Our board absolutely hated that memory and it was a fight to get even 1000MHz reasonably stable at 8-8-8. No problem we figured, it happens, let's move on to the Ballistix which are based on similar but slightly different ICs. Again, we found a limit of around 1015MHz for full stability at any CL8 timing set. Again, this is a kit of memory that clocked to 1060MHz completely stable on the 790i. For us on the Rampage Extreme, we couldn't get over 1030MHz even dual 32M stable regardless of voltage, and at 1030MHz we were only at 1.95v. Needless to say, some searching in forums has found a large amount of memory incompatibilities with this motherboard when it comes to high end overclocking and some even at stock frequencies.

In the end, we decided to see how low we could take the volts and still get 1000MHz stable with the Ballistix kit at 8-7-6. As we can see above, vDIMM dropped through the floor and vMCH was at a relatively low 1.51v. The most impressive factor out of all of this is the NB temperature which was at 60C for most of the stability testing. The A/C in the room accidentally got turned off and when we saw the temps climb. we decided to see how long it would go. Much to our surprise, it handled this solid memory overclock at a very high NB temperature which is very impressive.

FSB Stability Overclocking

This is when things get out of hand, and by out of hand, we mean downright crazy. This screenshot was literally started within 15 minutes of firing the motherboard up for the very first time. It climbed to 600FSB so quickly and did it with tight timings for this FSB without so much as an effort on our part. Straight out of the box, stock cooling, and standard ambient cooling on the CPU was easily 600FSB 24/7 stable on this board and a monkey could have pretty much pulled it off. We didn't even bother trying for higher for full stability because what was the point. No one really needs to be running 600FSB, especially for full stability, so we ended it there. In the Extreme Overclocking section coming up, the 600FSB+ was quite handy having on tap though.

Overall Stability Overclocking

What else can we say, this board is simply unbelievable. Rocking 4.3GHz with a good E8600 for 24/7 isn't the impressive thing, 477FSB is nothing really exciting, DDR3-1908 7-6-5 is nice but nothing crazy. There is, however, one thing in that screenshot that is absolutely impressive. Performance Level 6 (tRD) at 477FSB with only 1.46v being 24/7 stable is just jaw dropping and for those that have been clocking X38/X48 boards for the better part of the last year, it is just un-heard of. This board is absolutely legendary in our opinions because it has the ability for an all out benching monster, and can do the little things that make this motherboard extremely fast for a 24/7 system. We have just seen that the 24/7 clocks are nice, later we will see if we can validate that "all out benching monster" claim.