2GB RAM works but not 4GB

The problem is:

I have 4 ram chips for 1GB each. When I connect over 2GB of RAM to my PC, it freezes the PC, only fast in the beginning. This happens only when I have more than 2GB ram, when I have 2GB or less, everything works fine.

Have visited and checked the BIOS, which runs all of 800MHz, would actually run at 1066 MHz, but I can not higher up (all the components are added to cope with the speed and 4gb of ram).

Motherboard: Gigabyte GA-P31-DS3L
CPU: Intel Core 2 Duo E4600 2.4GHz
RAM: Kingston HyperX 1GB PC8500 DDR2

Running ubuntu desktop.

Change the frequency using divider in bios and give memory chips right voltage 2.2 V = +0.4 in the bios.

Update your bios.

There is really no point, provides little/no performance gain. But you may want to adjust in the same bus a few MHz and actually get a performance gain.

But it is running at 533MHz, how do I get it up to 1066MHz?

Could take up 533 to 800 each, but then it started to get full of warnings, etc., can be damaged?

So I should have it at 533 or take something in between for the items, 633?

Give the right voltage of memory chips?

See if you can find a setting like North bridge voltage or MCH-voltage, adjust it up a few notches

Otherwise, as often solves an update bios of many memory problems

Has +0.4 V in which one makes the excitement.

To see if I can find what you said, find something called system memory multiplier.

Do not have the latest BIOS drivers with Ubuntu?

Bios has nothing to do directly with OS/Ubuntu. See manual/motherboard manufacturer's product page.

System ...... use to adjust the relationship bus/memory. Thus the frequency of memory in relation to bus

Find the system memory multiplier that you use to adjust the memory.

2.9 CPU Host Clock Control to enable, then change the rate to below the CPU clock.

Note: 250 should at least not be a problem. Gives you the 3GHz CPU

CPU Clock stands at 2.66GHz, memory MHz stands at 1066MHz and +0.4 V.

Thanks for the help