OK. A lot of people here can clarify things for you as well as I, but I'll take this opportunity while waiting for "certain people" to speak on TV from Denver.
At this stage in the game, with the Penryn-Wolfdales such as the E8600, you have a processor that is set to run at a stock setting of 333 Mhz CPU_FSB or 4 x 333 = 1,333 Mhz FSB for the system. The stock speed specification for the processor is 3.33 Ghz, so implicit in that information is that the stock multiplier for the processor is 10. 10 x 333 Mhz = 3.33 Ghz.
Since the memory that would match the CPU_FSB in a 1:1 ratio is double-data-rate (DDR in the DDR2 specification) memory, the rated speed for such a memory kit would be 2 x 333 = ~ 667 Mhz or DDR2-667.
But nobody here would spend the money on DDR2-667 when they can have DDR2-800 or DDR2-1000(or 1066), because even with the processor at stock speed, the motherboard should auto-configure to run either memory specification in a "native-mode" of DDR2-800 as default. This would mean that the CPU : RAM ratio is not 1:1, but instead, 5:6. This is what would happen initially if you just plug in the CPU to its LGA775 socket, pop on the heatsink-fan, socket the DDR2-800 or DDR2-1000 memory, hook up the motherboard and start it up. As a footnote, the CPU : RAM ratio is a comparison of the CPU_FSB and the memory FSB, or one-half the memory's DDR speed of 800 -- which is 400. 333 / 5 = 66.6, and 66.6 x 6 = ~ 400.
Now -- with DDR2-800 modules, you could independently and manually choose in BIOS setup an FSB setting of 1,600 Mhz instead of the default 1,333 with a memory DDR speed of 800, and this would give you a CPU : RAM ratio of 1:1. That is, the CPU_FSB would then be 400 Mhz, and the RAM_FSB would then be 400 Mhz.
But to do this, you would need to patiently and carefully adjust the CPU_FSB about 5 Mhz at a time without any guidelines or guesses from other users, and either a stress-test error in PRIME95 or instability leading to a BSOD would require that you increase the VCORE voltage of the CPU incrementally and just enough to provide stability at the new system FSB that has increased by 5 x 4 = 20 Mhz. At the same time, the memory DDR speed would have to increase by 5 x 2 = 10 Mhz.
And as you might move slowly up a notch at a time, you might find that increasing the RAM voltage a notch would be required, because you are increasing the speed and therefore the stable power requirement for the RAM. So you would begin to juggle increases in your speed settings, increases in CPU VCORE voltage, and increases in RAM voltage to achieve higher and higher overall speeds without increasing the voltages more than necessary.
And you would have to limit these efforts to avoid stressing either the CPU or the RAM with so much voltage that the component's life would either be shortened, or immediately terminated.
So you would get an idea of the voltage tolerance of both CPU and RAM by consulting the specs of the item at the manufacturer web-site. For instance, the retail box "maximum voltage" for the E8600 might be 1.25V, although anything up to 1.4V might be "safe," but you might want to choose your own "red-line" and decide that you won't over-volt the processor beyond 1.35V. And anyway, what you "set" the VCORE to might not show a monitored reading as great, or might not increase the real voltage as much as the setting would make you anticipate.
Similarly, with the RAM voltage, you might make note of its maximum voltage spec -- many RAM kits are spec'd at 2.1V or 2.2V. But companies spec their RAM differently. Corsair might say "tested at 2.1V" with a 5% tolerance meaning you could probably run the voltage up to 2.2 without worrying much about the part's longevity; you might "take a walk on the wild side" and push it as high as 2.3 at your own risk. But with modules made by Crucial, their spec might be an absolute, and you might find by reading user comments and benchtest reviews that going over the 2.2V spec at all would cause the RAM kit to die in a few months.
With DDR2-1000 modules, you have a lot of wiggle room to over-clock at a 1:1 ratio, and you'd be limited by both the CPU and the motherboard rather than the RAM. Or, you could change the CPU : RAM ratio to run the CPU somewhere above 1,333 FSB, so that the RAM's DDR-speed moves above 800 toward 900 or 1000.
Does that help you? I suggest you read Graysky's Guide to overclocking stickied on the CPUs and OverClocking forum. Your "ambition" of OC"ing the E8600 from 3.33 Ghz to 3.6 is reasonable, modest, and less than it can probably safely go. It is just about exactly an 8% over-clock. You should probably be able to achieve 20%. If you choose a 1:1 ratio, you would have to over-clock from 3.33 to nearly 4 Ghz, or 3.996 Ghz. With DDR2-800 modules, this would give you exactly the ~ 400Mhz RAM-FSB that you need to get a DDR speed of 2 x 400 or 800 Mhz.
Find the thread on the CPUs and Over-Clocking forum where people are posting their results with the E8600. This will give you a better idea of what voltages to use to get to those speeds before you fine tune them for the desired speed. The rest of it involves a trade-off between RAM voltage, RAM timings and RAM speed. Higher RAM speed and tighter (lower) latency timings mean higher voltage -- hopefully within the maximum warranty spec. You might achieve higher speed at the same or lower voltage if the latency timings are looser (higher).
FOOTNOTE: My choice of wording and how BIOS setup adjustments are made reflects my familiarity with my own motherboard. I'm using a board with an nVidia chipset. You may have a board with an Intel chipset. How the INtel board might auto-configure memory is something that I am not personally familiar with. Some boards may allow you to choose a CPU : RAM ratio directly from a menu, or give you the option to simply key in the speeds you want to try. Some boards have an option to link or unlink the system FSB from the DDR speed. You need to read the motherboard manual WELL and the sticky I mentioned on "CPUs and Over-Clocking" before you start fiddling around with the BIOS setup options.
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