What Memory Should I Use ?

Have you run memtest86+ on each stick to determine if any of them are defective?

I have heard that you should not use more than three sticks of OCZ3G1600LV6GK with this motherboard when attempting to run the RAM at 1600.

Have you been manually setting all timings and voltages? Have you also tried setting QPI to 1.35 Volts?

Of course you can use a brand other than OCZ. Other brands I would consider are Corsair, G.Skill, and Patriot.

Hi ko888,
Thanks for your help and quick response. I have to admit first I have little tech knopwledge or experience with a BIOS etc. That's why I picked this forum. This build is the first time I ever set anything up in a computer other than simple Windows changes. I downloaded Memtest86 but had no idea on how to either install or run it. The readme file was not easy to understand. I went into my BIOS AI TWEAKER menu and here are the settings I currently have after I was overclocked to 3.4.
From DRAM TIMING CONTROL down, everything is set to auto:

AI OVERCLOCK TUNER - MANUAL
CPU RATIO SETTING - AUTO
INTEL SPEEDSTEP - DISABLED
BCLK FREQ. - 170
PCIE FREQ. - 100
DRAM FREQ-AUTO
UCLK FREQ - AUTO
QPI LINK DATA RATE -AUTO
CPU VOLTAGE - AUTO
CPU PLL - AUTO
QPI/DRAM CORE VOLT. - AUTO
IOH VOLT. - AUTO
IOH PCIE VOLT. - AUTO
IGH VOLT. - AUTO

DRAM TIMING CONTROL"

1ST INFORMATION: 6-6-6-18-3-44-6-5-16-0
DRAM CAS# LATENCY
DRAM RAS# TO CAS# DELAY
DRAM RAS# TO PRE TIME
DRAM RAS# TO ACT TIME
DRAM RAS# TO RAS# DELAY
DRAM REF CYCLE TIME
DRAM WRITE RECOVERY TIME
DRAM READ TO PRE TIME
DRAM FOUR ACT WIN TIME
DRAM BACK TO BACK CAS# DELAY

2ND INFORMATION: 1N-0-0-60
DRAM TIMING MODE
ROUND TRIP LATENCY ON CHA
ROUND TRIP LATENCY ON CHB
ROUND TRIP LATENCY ON CHC

3RD INFORMATION: 6-6-13-9-9-9-7-6-4-7-7-4
DRAM WRITE TO READ DELAY (DD)
DRAM WRITE TO READ DELAY (DR)
DRAM WRITE TO READ DELAY (SR)
DRAM READ TO WRITE DELAY (DD)
DRAM READ TO WRITE DELAY (DR)
DRAM READ TO WRITE DELAY (SR)
DRAM READ TO READ DELAY (DD)
DRAM READ TO READ DELAY (DR)
DRAM READ TO READ DELAY (SR)
DRAM WRITE TO WRITE DELAY (DD)
DRAM WRITE TO WRITE DELAY (DR)
DRAM WRITE TO WRITE DELAY (SR)
All of the above are set to AUTO. The "INFORMATION" lines are grayed out. When I tried to set the DRAM BUS VOLT to 1.65, it would only print 1.66 in red and warn me anything over 1.65 would damage the processor. Again, I know nothing about these settings or what they mean, nor what to change them to. I thought AUTO would take care of that for me. Any info you give me will be greatly appreciated. Thanks again. Tom

Page 2-12 of the P6T Motherboard manual states "Due to Intel spec definition, X.M.P. DIMMs and DDR3-1600 are supported for one DIMM per channel only." This means only three memory modules maximum when running at 1600.

Why are you overclocking to 3.4 GHz when you haven't even proven that your system is stable at the stock clock speed of 2.66 GHz?

From the info you've posted I don't see any resemblance to OCZ's specs for this memory.

Since OCZ's specifications for the OCZ3G1600LV6GK are:

CL 8-8-8-24 (CAS-TRCD-TRP-TRAS) at 1.65 Volts

you need to go into the BIOS setup and manually set the memory speed, timings, and voltage if you ever expect to run the memory modules at its rated specs.

Yep. I have the same mobo, and only 6GB of same memory!

If you want more (why would you?) you have to underclock it to DDR3-1333. I THINK!

Unless you are doing alot of Video Editing or CAD, 6GB is plenty! I'd return 6GB and go with what you are doing: DDR3@1600, OC i920 @ 3.2Ghz.

P.S. Yes, after I "upgraded" from 3GB of Crucial XMS DDR3-1600 memory, I have heard that OCZ memory is not all that great, with or without Asus mobo. I haven't had any crashes, but my i920 is still @ 2.67GHz. I haven't OC's, yet.

AND, I thought it was CAS7, but it's CAS9. Or I thought it was CAS6, and it's CAS8. I'm not on my machine right now.

Yes, I saw that same statement in the P6T manual and asked the guy who is helping me build this system by talking me through it if I was OK with the memory and 12 gig of it (6 DIMMS) and he said he had the same config with no problems. He had me remove 6 of the 12 gig when I told him what was happening with the crashes. I think he planned on overclocking more but stopped at 3.4 as the first stage when he realized I was still having stability issues. I know he is busy with other clients and I hate to keep bothering him regarding my problem. Remember, I am new to all of this. I guess I need to be talked through in simple steps by someone knowledgable and patient. That's why I listed my exact settings above. I simply want to know what numbers to plug in and where. CL 8-8-8-24 CAS, TRCD, etc. mean nothing to me. I need to know where to put them.