Annoying issues when setting memory speed to 1600

I have a few possibly related issues with my new build:

Bloodrage mobo
i7 920 (D revision)
6Gb Mushkin Red Line 1600
Geforce 295GTX
1000w Antec Power supply

These are not critical but annoying issues that I have been trying to phase out and its driving me insane getting to the bottom of the issue! Any help would be appreciated

1. When Vtt is set to +140mV or higher, a cold boot results in power shutting off within 1 second, but a second press of power button boots machine fine. This only happens when power is turned off at power supply and Vtt is +140Mv or more. Flakey PWM? Flakey power supply? Flakey mobo? Flakey CPU?

2. When memory speed is set to 1600mhz the mobo ALWAYS fails to boot on the SECOND attempt at waking computer from sleep. First time fine, second time, never wakes with mobo debug code of C0. Flakey CPU?

3. I have noticed that the Bloodrage DMI always shows a 32bit memory error, even having tried three sets of DDR3, although memory count and usage is always solid.

32-bit Memory Error Information (Type 18)
----------------------------------------------------------
Error Type Other
Error Granularity Other
Error Operation Other
Vendor Syndrome unknown
Memory Array Error Address unknown
Device Error Address unknown
Error Resolution unknown

Other than these issues the machine runs absolutely fine, the technician side of me wants to get to the bottom of this and its driving me insane! Any thoughts or ideas would be much appreciated!

I have reasonable OC experience and just cant get to the bottom of this!

Many thanks in advance for useful advice!