Conclusions and Final Thoughts

Our experience with the ASUS Rampage Formula has been tremendously enlightening thus far. Although we can confidently claim a long-standing familiarity with MCH Read Delay (tRD) and its affect on overall system performance, this motherboard provided us exactly the foundation we needed to develop our current understanding of just how some of these previously elusive settings really work. There is no reason why any enthusiast should not be able to arm themselves with this information in their quest for the perfect overclock based on overall system performance. We sincerely hope that the Rampage Formula is the first of many boards from ASUS to incorporate this kind of great innovation. We have grown accustomed to using it now, and we don't want to go back to the old methods of manipulating tRD.

The Rampage Formula's layout is as close to perfect to possible - water-cooling enthusiasts will have no problems fitting two ATI graphics cards in Crossfire, even when installing full-coverage water blocks. Through-hole mounting for the Northbridge and the ability to remove the stock cooling solution without disturbing the portion covering the MOSFETs in the power delivery circuit is especially nice. Fitting an after-market heatsink on the MCH will be simple and straightforward. Then again, this may not be necessary; we actually found the X48 to be cooler than the X38 in the production level boards.

The ability to use DDR2 is another great benefit to consider when selecting an X48 board. Again, ASUS has made the right choice in this arena and has decided to provide separate solutions based on each memory type. For the ultimate in performance, though, we suggest you check out DDR3 based configurations if you can afford it.



We anxiously await the impending availability of this board; we know that its release - and that of its DDR3-based "Extreme" brethren - has the potential to usher in a new round of 3D performance records from today's top overclockers. The early maturity of ASUS' BIOS coupled with the capabilities of the Intel X48 chipset make a fantastic combination for achieving absolute top speeds. For those of us more firmly grounded in reality, rest assured that we have a hard time finding reason not to recommend the use of this board in even the most demanding new systems.

It would be ignorant of us not to expect other companies such as MSI, abit, DFI, and Foxconn to follow suit with the introduction of their top-end X48 boards. In fact, just last week we took an in-depth look at the Gigabyte GA-X48T-DQ6 and what it had to offer. Although it's not quite as strong out of the gate, given time we expect BIOS improvements to close the gap. The Gigabyte board also uses newer DDR3 technology, so whether or not ASUS' comparable board will experience the same types of problems remains to be seen.

One thing is for certain, Intel and ASUS have teamed up to bring us another great overclocking choice that sets a new standard in the market. Early reports of limited performance improvements may have tempted you sit out the X48 release. Based on our results from the ASUS Rampage Formula, we will go on record now and reject our previous position. We will be running X48 boards in our personal systems; what about you?

How to Choose an Appropriate Memory Configuration
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  • Orthogonal - Friday, January 25, 2008 - link

    Just so I understand this correctly, due to the path the data and clocks must travel throughout the devices as explained on page 5, even though you can increase the bandwidth of the Memory modules, the MCH is ultimately the "bottleneck". Historically we falsely assumed higher bandwidth and lower CAS latency translated to better data throughput, but since tRD increased along with it, it was essentially wiped out or unused bandwidth. Now we try to lower tRD as low as possible to reduce MCH latency as it performs the "Clock crossing procedure", which is why the 400Mhz FSB with the lowest tRD latency gives the best data throughput.

    Also, does this mean that in your "Best Pick" DDR2 configuration summary that the two A+ choices highlighted in Green will effectively result in about the same performance since even though DDR2-1200 has more bandwidth than DDR2-1000, since the tRD=5, they will have the same Trd Delay (12.5ns).
  • Aivas47a - Friday, January 25, 2008 - link

    I'm glad to see Asus implementing these new memory phase adjustment options in the bios. Now if they would provide a greater ability to fine-tune GTL reference voltages I would be a happy camper. GTL is a key setting for quad core overclocking success as Raja has helpfully explained in his DFI P35 review. The selectable percentages Asus currently provides are too crude and don't go high enough.
  • mrlobber - Friday, January 25, 2008 - link

    FCG, your article just flat out rocks, thanks for this one, we needed it badly :)

    One question about the previous Asus boards: X38 and also P35, which lack the exact tRD manipulation, providing the Transaction Booster stuff instead. As far as I understand, your analysis about the default tRD values set by different default fsb and memory divider combinations could also be used to determine the starting tRD value at least for the X38 chipset as well in a pretty straightforward way, and from that point being able to offset the tRD with Transaction Booster up or down to control it as necessary? (P35 would have different default tRD's, but the underlying principles should stay the same?)

    And, by making appropriate changes in x values if needed, your POST / no POST inequality should stay applicable as well, right?
  • kjboughton - Friday, January 25, 2008 - link

    All true, although we did talk about how these straps at one time had default tRD values associated with them, the difference has become that these default values are now usually based on the real underlying requirements, such as FSB. Now, exactly how each motherboard vendor sets up and implements this value has a lot to do with how their motherboard falls out in comparison testing. With that being said, boards that perform better generally make use of lower tRD values by default. And because X48 is a speed-binned version of X38, which is superior to P35 with it comes to MCH overclocking, it is also safe to say that the higher-end chipsets will allower the same (or lower) tRD values at FSB levels where the other chipsets may fall flat on their faces. Make sense?

    Regarding the 'Test POST Equation' - absolutely, I know those equations to be true for X38/X48 but I wouldn't doubt if they ended up being exactly the same for say, P35. A little bit of testing should validate this assumption... ;)
  • Orthogonal - Friday, January 25, 2008 - link

    Can we expect a similar analysis and optimization of strappings, timings etc... when an X48 DDR3 compatible board is released?
  • kjboughton - Friday, January 25, 2008 - link

    Yes, the will be an easy bridge to make. DDR3 is very similar to DDR2 and in a lot of respects is a simply extension of the logic already developed. In any case, we will provide this information for reference when the time comes.
  • daddyo323 - Friday, January 25, 2008 - link

    I've overclocked a couple cpus before, and each time, I had stability problems due to memory.

    I have built many systems, but since gave up on overclocking... these new Cores and chipsets look like they were made for it...

    My question is, was that CPU stable at 4ghz, and could we have a chart on which settings to set, exactly... I wonder how far we can push this platform with the air cooling.
  • kjboughton - Friday, January 25, 2008 - link

    Everything you want to know, about more, about this CPU can be seen here: http://www.anandtech.com/cpuchipsets/intel/showdoc...">http://www.anandtech.com/cpuchipsets/intel/showdoc...

    We used the same CPU that can be read about in the above review. The short answer is yes, we were completely stable at 4GHz with just 1.28V real under load.

    Cheers,
    Kris
  • Quiksilver - Friday, January 25, 2008 - link

    Has there been an ETA on the release date of the X48 chipset? I thought they were supposed to come out in December but they never appeared and this would be the second X48 preview I've seen for AT. Also I remember seeing a flow chart somewhere that had DDR2 & DDR3 being the differences between X38 and X48 of which X38 had both but now it seems X48 has DDR2 as well but will the DDR2 boards be available at launch or are they coming later on?
  • Gary Key - Friday, January 25, 2008 - link

    ASUS is telling us mid-February for the X48 launch now. Gigabyte and MSI have confirmed that also, but we have had dates confirmed about a dozen times over the last two months and it always seems to change about three days before the next "official" launch. ;)

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