New chips from ncix.com(place i bought them from) have 8 chips per stick
Old chips from other place has 16 chips per stick.
1 new chip slot 1 3473 mb/s
1 old chip slot 1 3908 mb/s
all 4 slots taken old,new,old,new 3487mb/s
These are on stock settings 1066mhz 5-5-5-15 2.2v
Clearly, those results confirm what ScanIAm said. But worse still, with the 4GB configuration, the memory is being run in single channel mode. Ouch.
Yep, get 'em replaced. Hopefully, you've not been a victim of an earlier customer doing a swap. Otherwise, they may think your the one trying to scam them. 
BTW, a quick look over the [crucial.com warranty page] seems to have worrying language where they state that any claim to warranty is only redeemable by the original purchaser. There's no mention about whether resellers are this original purchaser, rather than you.
 I saw one person doing a contents swap at a warehouse pickup counter. He had the clerk collect one order, then suddenly remembered he had another order, and when they went to pick that, the mongrel performed his scam. When the clerk came back, he said he did want one of the items from the first order, and so the clerk put it pack into stock, without checking anything. Slick. Well, until I told the clerk when I was being served...