Can you put 555Mhz ram on 667MHz slot

accesgranted1

Honorable
Oct 15, 2013
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hi guys i was wondering if i can put a 555MHz memory stick on my 800 or 667Mhz slot (sory i havent really paid atention)so i bought 1 555Mhz stick and 1 667MhZ stick they are both ddr2 can i put them in the ram slots im scared to not damage something...are they compatible?