Overclocking Q6600 with DDR3 1333MHz two types Dual Channel?

Hi, I'm OC noob, but I pretty much understand hardware. This is my first time to try an overclock.

Specs:

Asus P5P43TD (two slots for DDR3 in dual channel up to 1600)
Intel Q6600 (2.4Ghz)
2 x Corsair 2GB VS2GB1333D3 in A1 and B1
2 x Corsair CM3x2048-1333C9CHX in A2 and B2

My goal was to use the full potential of my memory by clocking it to 1333 MHz. By default the system has it at 1066 MHz, because the CPU is 2.4 GHz, I think I pretty much understand why. So I need to set the FSB at 333 and CPU at 3.0GHz so I can have my memory at 1333.

So I've read this guide and I've set the following:

CPU Rating: 9
FSB: 333 MHz
FSB NB: 333 MHz
PCI: 100 MHz
DRAM Frequency: 1333 MHz
DRAM Timing Control: 9-9-9-24

That's pretty much what I changed, everything else I left to auto. The PC booted, windows worked normal and it seemed like the OC was successful. However when I ran CPU-Z to check if everything is normal the first pair of my modules (the VS2GB1333D3) ran perfectly on 1333MHz. The second pair (CM3x2048-1333C9CHX) however still ran at 533MHz or 1066. I switched their places with the other pair from A2/B2 to A1/B1 and again the clock on the same two modules was 533MHz

Now I'm confused. What's wrong with the Corsair CM3x2048-1333C9CHX so they can't be clocked to 1333MHz?
1. How can it run like this? One dual channel on 667, the other 533?
2. Why won't this memory get clocked to 667 ?? It has almost identical specs as the other pair.

I'm puzzled here. What seems to be the problem??

Any recommendations/suggestions would be highly appreciated!

Are you looking at the SPD tab or the Memory tab in CPUz?
I'm unaware of any systems that can run the RAM at different speeds, and am also unaware of any way to select which slot you're seeing the current speed of in CPUz.
The "Memory" tab has the current speed in it, the SPD tab shows you the SPD information on the stick of RAM you select.

Bobnova said:

Are you looking at the SPD tab or the Memory tab in CPUz?
I'm unaware of any systems that can run the RAM at different speeds, and am also unaware of any way to select which slot you're seeing the current speed of in CPUz.
The "Memory" tab has the current speed in it, the SPD tab shows you the SPD information on the stick of RAM you select.

Click to expand...

I'm looking them at the SPD tab yes. Slot 1 and 3 were 667 and 2 and 4 533. Memory tab showed 667.

So what is the SPD information anyway? How can it show one pair of my modules as 667 and the other 533? Would you care to elaborate?

Thanks for your lightning fast reply!

SPD stands for "Serial Presence Detect", which explains roughly nothing.
What the stuff in the SPD tables is used for is setting the memory speeds when you set the ram to AUTO, and/or when you first plug it into the motherboard. If you look on the sticks of RAM you'll see a tiny (<0.25" square-ish) little 8pin chip, that's the SPD chip. It's an EEPROM storage chip that has the SPD data in it.
The motherboard / BIOS looks at the table(s), looks at it's own abilities, and then uses that information to set the speed at which the ram runs at.

What you have there is one kit of RAM with SPD tables for 667MHz (1333MHz) and one kit of RAM with SPD tables for 533MHz (1066MHz).
The SPD tables don't always match the sticker on the RAM or the actual ratings, sometimes they're completely out to lunch. What it is, essentially, is a list of speeds and timings that the ram is guaranteed to run at. In theory anyway

The Memory tab tells the current speed the memory actually running at, 667MHz in this case, which is the 1333MHz you were aiming for.

So what it comes down to is, you've accomplished exactly what you set out to do, despite the SPD tables not matching. As such, good work! Now of course you could try pushing the FSB (and hence, memory frequency) higher and see if those kits will do 1600MHz (800MHz in CPUz).
Do be aware however that pushing RAM speeds is a very easy way to corrupt a windows install. My record is 11 minutes between finishing a windows install and killing it playing with RAM! That's not the benching team record though, if I recall the record is four minutes.
The message there is, don't push extreme memory clocks on your 24/7 OS