Derbixrace,
Sorry ... don't shoot the messenger, but you're about max'd out.
Intel's 975X northbridge chipset is inherently FSB limited. It doesn't scale well with 4 memory modules or with quad cores. Even with 2 x 2 GB memory and a dual core, such as the E6600 or E6850, both of which have 9x multipliers, and even with FSB modifications for nothbridge voltage and cooling, it's very difficult to reach or exceed a stable 425 FSB overclock.
Intel's P965 northbridge chipset was a huge improvement in overclock ability, often capable of exceeding 525 FSB, however, it didn't have all the excellent features of the 975X. The 975X was Intel's flagship chipset until the X38 was released.
Regardless, the most suitable quad core processor for overclocking on the 975X chipset motherboards is the Q6700, because of the 10x mutiplier, so that 3.6 Ghz is achievable with 10 x 360.
Comp