dual channel failure & single channel errors

[Ed W.]

PC seems to run fine in single channel mode but monitor reports no input in dual channel mode and memtest86+ lists from 1-3 errors per pass in single channel mode. Motherboard (Gigabyte P43T-ES3G) can't be set for the 1.65 volts required by the RAM (2x2 of OCZ3P1333LV4GK PC3 10666). The mobo voltage choices are 1.6 or 1.7 volts. I have tried both and increased the MCH voltage from 1.1 v to 1.2 v, but so far can't get it to run in dual channel mode at all and single channel mode seems to run fine but I still get errors in memtest86+. Also tried optimized Bios settings and loosened memory timings (from 7-7-7-16 to 8-8-8-27 and tRFC 60 to 70) and reset Command Rate from 0 to 2.

CPU is Core 2 Quad @ 2.4 Ghz, PSU is rated at 400 watts, Video card is Gigabyte GT220. Any help would be greatly appreciated.

[tgalati4]

Try different RAM. If you get errors with two other brands of RAM, then you have a defective motherboard.

[Ed W.]

Thanks tgalati4, for the help. I will probably have to buy some more memory to do that. So it will be a week or so before I can report the results. What are the odds on both sticks of memory being bad?

Also I noticed that when one stick of memory is in either slot 1 or 2 that memtest86+ sees it correctly as DDR3, but when it is in either slot 3 or 4, memtest86+ sees it as DDR2.