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My previous laptop had 4x4GB 1066 Mhz DDR3.

My new laptop instead has only 2x4GB 1600 Mhz DDR3.

Using dmidecode I gather my FSB is set to 2300Mhz.

Max Speed: 3800 MHz
Current Speed: 2300 MHz

2 questions:

  • Can somebody confirm I can safely add two "old" 1066Mhz modules to my new laptop before I treat myself to faster DDR3 modules?
  • I understand this should not slow down the faster 2 1600 Mhz DDR3 modules. Correct?

If this is of any relevance, I'm running Linux Mint Maya.

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If you put slower memory in your computer then ALL memory will be ran at that speed. – Ramhound Aug 28 '12 at 11:34
up vote 2 down vote accepted

It will slow it down.

  • All RAM modules work at the same speed.

  • The best way this is done by the system is make them all work at the slowest speed.

  • You can definitely add your older RAM modules safely to you new laptop.

  • However, if you add 2 x 4GB modules @ 1066Mhz, the 2 x 4GB modules @ 1600Mhz will also work @ 1066Mhz

  • Ideally, all your RAM modules should be identical for best performance.

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Just to clarify, it'll slow down the RAM modules, not the computer itself (at least not perceivably). – Indrek Aug 28 '12 at 11:36

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