DDR2 1066 and 1200 Mhz don't work together

[synape]

I have recently built my new system. The motherboard is ASUS P5QPro and 2x1 GB OCZ DDR2 1066 Mhz RAM is installed in dual channel mode.
The problem is, when I try to install my Kingston HyperX 2x1 GB DDR2 1200 Mhz RAMs to make it 4GB's of RAM in total, the motherboard does not start (no signal on monitor).
Is there any way to make them work together. If I new that they wouldn't work together, I wouldn't buy the new OCZ RAM's

Murat Okay

 

[techgeek]

You should never try to mix and match different brands / speeds of RAM. The problem is that they often require different operating voltages, and timings.

That said, it isn't impossible. If you have all the BIOS settings pertaining to your RAM set to AUTO, there is where you need to start. Obviously for this step you'll need to run just one pair. Find out what the operating voltage for each pair is, next find the timings needed for each pair. In the case of voltage, you need to set it to the higher of the two voltages (or sometimes you can get away with splitting the difference). Next set the timings to the lowest common denominator. For instance if one pair operates at 4-4-4-12 and the other operates at 5-5-5-15, you should use 5-5-5-15. Once you have adjusted the settings in your BIOS, reboot with just this pair. If it POST's that means that the first set tolerates your new setting. Next shutdown and unplug your computer, install the rest of your RAM and see if it will POST. If it does, it couldn't hurt to run memtest just to be sure that everything is good. If it doesn't POST, you may have to tweak the above mentioned settings. If you can't resolve settings that work with both pairs installed in a relatively short amount of time, lesson learned (ie top paragraph). Hopefully you can return the OCZ's for an exchange or refund in that case.

Hope that helps.

 

[synape]

Thank you very much for the reply.
I'll do what you have said and see if that works.