Intel Core 2 Extreme QX9770

Just how extreme is Extreme? Josh Collins runs the numbers on Intel’s latest.

In issue 83 we took a look at the then recently released QX9650. Now, only a couple months later, we have another 45nm quad core processor to add to the Core 2 Extreme product range in the form of the QX9770.

Now while most individuals have been awaiting the non-extreme edition 9000 series 45nm quads from Intel, this release still sparks interest. The reason for this is the move to a 1600MHz (400MHz quad pumped) Front Side Bus (FSB). This increase in FSB means greater bandwidth, but all enthusiasts and overclockers already knew this and many of us have had our older 266MHz chips running happily at 400MHz and higher. The difference here is that the new QX9770 comes with a 400MHz FSB as stock– it could be said that the progression from 266MHz to 333MHz and then now on to 400MHz is more of a recognition of the frequencies enthusiasts have been playing around with for some time.

Sitting well above the QX9650 in the binning process, the QX9770 selections would is the cherriest of the cherry-picked. To really test this theory, we decided we’d take to our victim, ahem... processor, with a Noctua NH-U12P air-cooled heatsink. A slight removal from our usual sub-zero antics of the latest and greatest processor but we’ve seen what can be done with the QX9650 45nm quad under sub-zero -- frequencies between 5.2GHz and 5.4GHz at -110 degrees Celsius to -140 degrees Celsius. So the big question is what can the more mainstream expect from such a chip?

With the QX9770 strapped under this metal chunk of air cooling goodness we got to pushing the silicon. Once we got our bearings with the stock 400x8 configuration the next challenge was to achieve the same end frequency but using a 7x multiplier. This meant dropping the multi to seven (obviously) and then raising the FSB to 457MHz to compensate for the decrease in multiplier. We were happy to see the processor comfortably crunching away at the numbers as it sat nestled in an ASUS P5E3 Deluxe with a pair of Corsair Dominator DDR3-1800 C7 memory modules.

To find the maximum FSB we dropped the multiplier again to 6x and found the system would hang just above 475MHz, yet bench comfortably at 475MHz. With the difference between 475MHz and the previous 457MHz we raised the multiplier back up to seven. As a result, this also reigned in an end processor frequency of 3325MHz on all four cores.

Next we tested high CPU frequency clocks while maintaining a relatively high FSB frequency. This lead us to 450MHz FSB and a 9x multiplier with an end result of 4050MHz – not half bad for air cooling, and it let us achieve some pretty satisfying benching results. The system was running just shy of going sub one minute in the Super Pi 4M test and sub ten seconds for wPrime 32M; now was the time to seriously tweak.

After some BIOS tinkering with the FSB frequency and CPU multiplier, as well as the memory divider/frequency and latencies it was time to test again. At a whopping 4.3GHz on air cooling the chip simply flew through the benchmark suite. As well as doing the suite with ease, the system just so happened to score below a minute in Super Pi 4M and less than ten seconds in wPrime 32M.

The CPU ended up topping out at a maximum of 4375MHz. We attempted to push even further using SetFSB but found ourselves at a wall, freezing at 4400MHz – we’ll leave this and above until sub-zero time occurs.

As mentioned the testing of this processor was done on the ASUS P5E3 Deluxe motherboard. The CPU was originally destined to be tested on the GIGABYTE GA-X48T-DQ6, however we found the BIOS was not yet fully capable of taking advantage of the QX9770, all the while operating fine with the QX9650. Be sure to keep this in mind if looking to purchase one of these chips. Additionally be mindful that the product development cycle can, and often does for the enthusiast, move into the live product cycle. The GIGABYTE GA-X38T-DQ6 had initial issues with the QX9650 but later grew to be a strong overclocking contender. Having tested on the F3d and F4d BIOS for the GA-X48T-DQ6 and seeing a lot of potential, we can only conclude that the board and the technology involved will come of age before it gets into the hands of the masses.

Cherry picked as the best of the best, these chips certainly deliver within the air cooling realm and we’ll no doubt be seeing some respectively massive overclocks with the assistance of water cooling, phase cooling and the more extreme dry ice and liquid nitrogen cooling.