HDD performance slow after cpu overclock

Hello,
I'm running an Asus P6TD V2 with an i7-960 @ 3.8 GHz, 6GB Crucial Ballistix 8-8-8-24 triple channel memory on win 7 x64 with an intel x-25m 80GB SSD (boot drive) along with several Seagate 1.5 & 2 TB 7200 rpm drives all on ICH10 SATA ports. As I increase the overclock on the CPU, the transfer speeds on the SSD seem to drop lower and lower. Any ideas what might causing this? ( btw, the RAM is running at 892 MHz for stability, although rated 1600 @ 1.65V, which is current DDR voltage)

If you drop your memory back to stock speed, does it make a difference? OCing your memory yields less performance gains than OCing your CPU and GPU. It also makes your system more unstable and often creates other unintended consequences.

I recommend you set your memory back to stock and focus on the other items (CPU and GPU) for OCing

To clarify, the 892 speed is the actual (doubled) speed - the actual memory clock is at 446 Mhz, verified with cpuid. If I try to run much higher, than that overclocked, the memory can't handle it (even though it's rated DDR2-1600 ) with bluescreening.
I can successfully run at 4.0 Ghz with memory bus speed set as low as MB lets me. It's just that my hard drive write speeds decline the higher I OC the cpu. Mostly shows up as a hit on the SSD speed, the conventional HDD's don't seem to be affected much if at all. ?? The PCI-E freq is locked at 100. The drives are all configured AHCI mode and running on the intel ICH10 sata ports, not the 2 additional Marvell sata ports. Have Intel RST installed along with the intel toolbox and all supposedly optimized, trim is active.