Vital Signs and Overclocking
Prior to benchmarking the new Core 2 Extreme QX6800, we spent some time with CPU-Z to see if there was anything interesting to report in regard to the CPU's default configuration. We then took some notes on temperatures and overclocking as well.
CPU-Z: Core 2 Extreme QX6800
Other than the Core 2 Extreme QX6800's clock speed, nothing much has changed since we last looked at the QX6700 a few months back. As you can see, both processors are based on the same B3 core stepping. The new QX6800 processor is also built using Intel's 65nm manufacturing process and it is clocked at 2.93GHz (11x266MHz), with 4MB of L2 cache per dual-core die, for a total of 8MB of L2 cache. There is also 128K of L1 cache (64K x 2) per execution core, for a total of 256K of various types of L1 cache (32K instruction and 32K data caches, per core).
Core 2 Extreme QX6800 Overclocked to 3.43GHz
After our initial inspection, we spent some time overclocking the new Core 2 Extreme QX6800 and had some interesting results. To overclock the processor, we used Intel's stock aluminum / copper PIB cooler. We bumped the CPU voltage up to 1.4v and set the memory voltage to 2.2v. We left the processor's multiplier at its stock value of 11x and raised the front side bus frequency until the test system was no longer stable.
In the end, we were able to take the QX6800 to just under 3.5GHz with an FSB of 312MHz. The approximate 500MHz overclock equates to roughly a 17% increase in clock speed, which respectable considering the mild voltage increase and the fact that we were using stock cooling. We were able to boot into Windows at speed approaching 3.6GHz, but we couldn't keep the system stable. Perhaps with more elaborate cooling and some more voltage, we would have had better luck.
We would also like to note that through all of our preliminary tests, we monitored the processor's temperatures via Intel's Desktop Control Center software. While idling at stock speeds, we found that the Core 2 Extreme QX6800 processor's core temperature hovered around 42C. And under load temperatures peaked at around 64C. Overclocking the CPU to almost 3.5GHz didn't drastically effect temperatures, but we did see a max of about 70C at one point, at least according to Intel's Desktop Control Center software.