I found this at the Corsair forum:
Recommended Corsair DDR3 memory for P45 chipset motherboards
We’ve received some feedback from users with motherboards based on the Intel P45 chipset who are unable to run 1600MHz stable, even with modules that are rated at that speed.
Testing done in our labs has concluded that users looking for the best overclocking results at 4GB on a P45-based DDR3 motherboard will have the best results using the following parts:
TW3X4G1800C8DF
TW3X4G2000C9DF
TW3X4096-1600C7DHX
The following part may top out at a speed short of 1600MHz on a P45-based motherboard:
TW3X4G1600C9DHX
The modules that we found unable to achieve 1600MHz on a P45-based motherboard were able to achieve 1800+ on an
Asus P5E3 Premium which uses the X48 chipset.
This issue is isolated to only motherboards using the P45 chipset.
Please note, this type of issue is something that’s often able to be remedied with a BIOS update from the motherboard manufacturer.
We’ll continue to update this thread as more information becomes available.
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Based on this info, I'd suggest getting your system fully stable at lower memory speeds using conservative (i.e. SPD) memory settings. Once your system is stable, you can then try higher memory speeds or using tighter memory timings.
The link to the memory review was with a P5E3 (X48) mobo and their XMS memory had a slightly different model # and SPD.
You might want to try the following setup:
8x440MHz = 3.52GHz
3.20Bx440MHz = 1408MHz memory speed
Using the "B" multiplier, you might be able to use tRD=7 (Static tRead Value) after doing initial testing with your current tRD=8.
**edit** Monitoring software often has "issues" with the 12 volt reading. You can try HWMonitor (v114) or SpeedFan (v438) to see if they do better. I wouldn't be concerned with the different Vcore temperatures at idle, let us know what the differences are under full loads.