Is it safe to mix ram?

[teapole]

I recently upgraded my motherboard to allow ddr3 ram, when I bought the motherboard I also bought a 4gb x2 ram package.

Basically, I still have 2 more slots and I want to buy another 8gbs, but I don't know if its safe to mix them.

I want to find some cheap, (30-45$) ram on newegg that's reliable, if anyone could direct me to that, I would greatly appreciate the help! Thank you!

 

[InvalidError]

In theory, yes. The BIOS should be selecting the lowest common denominator timings and clock speed so dissimilar pairs can work together.

In practice, mileage can vary since not every motherboard plays equally nice with any random pairs of DIMMs.

I have yet to personally run into dissimilar pairs problems but many others here have.