Conservative default settings are also mentioned in this notice, which are SPD timings of 5-5-5-15, although I had no issue posting the memory at 800Mhz with timings of 4-4-3-8 and only 1.8v on my Gigabyte 965P-DS3 (F7 bios).
Now moving on to overclocking the modules.
Note: In the following CPU-Z screenshots, the Tras is read incorrectly, it should be 8 instead of 9.
First I found the maximum frequency at which I could run the modules at default timings with the rated 2.2v, which turned out to be 450Mhz or DDR900. Increasing the voltage to 2.3v stabilizes up to 487.5Mhz or DDR975 without relaxing the timings. DDR975 was the highest frequency I was able to get the modules to run when using the 2.5x memory ratio (second screenshot only @ 480Mhz, benchmarks later @ 487.5Mhz).
Using the 3.0x memory ratio, we find a little more headroom when slightly relaxing the timings to 4-5-5-8. Still using 2.3v, this brings the modules up to 501Mhz or DDR1002, impressive. The system is completely stable at these settings, able to pass four 32M Super Pi runs in a row.
I was able to get the modules to post at up to 516Mhz with 4-5-5-8 timings at 2.4v, but no further relaxing of the timings or increasing of the voltage helped to stabilize this speed.
So, to summarize these results on my Gigabyte 965P-DS3 (F7 bios), I was able to achieve the following speed and timings at the given memory ratios of 2.0, 2.5, 2.66 and 3.0 (2.0 only being 457Mhz due to the FSB limitation of my motherboard).
2.0x = 457Mhz @ 4-4-3-8 2.3v
2.5x = 487.5Mhz @ 4-4-3-8 2.3v
2.66x = 487.5Mhz @ 4-4-3-8 2.3v -- behavior is the same for 2.5 and 2.66 mem ratios.
3.0x = 501Mhz @ 4-5-5-8 2.3v
Ok, now that we've managed to push these modules all the way up to DDR1002, it's time to see how they perform.
Intel Core 2 Duo E6600
GeForce 7950GX2 @ 575/1400
2x1Gb Stuper Talent PC6400 4-4-3-8 (T800UX2GC4)
2x512Mb G.Skill PC6400 4-4-4-12 (F2-6400PHU2-1GBHZ)
266x9 2.4Ghz @ 3.0 for ddr800 4-4-3-8
334x7 2.33Ghz @ 3.0 for ddr1002 4-5-5-8
400x8 3.2Ghz @ 2.0 for ddr800 4-4-3-8
390x8 3.12Ghz @ 2.5 for ddr975 4-4-3-8
334x9 3.0Ghz @ 3.0 for ddr1002 4-5-5-8
266x9 2.4Ghz @ 3.0 for ddr800 4-4-4-12
300x8 2.4Ghz @ 3.0 for ddr900 5-5-5-12
400x8 3.2Ghz @ 2.0 for ddr800 4-4-4-12
356x9 3.2Ghz @ 2.5 for ddr890 5-5-5-12
In the graphs, the Super Talent modules are labeled ST, and the G.Skill modules labeled GS.
To start off, a 1M Super Pi benchmark.
As we see in the graph, there isn't a huge difference here between 4-4-3-8 and 4-4-4-12 timings at 800Mhz. However, DDR800 with 4-4-4-12 or even 4-4-3-8 timings is nearly equal to DDR900 with 5-5-5-12 timings, at least in Super Pi.
Now let's continue on to page three for a few more benchmarks...