CAUTION problem on the number of chips

Ordered 2 bars 4GB each. Received 1 module with 4 chips per side (8 in total) and 1 module with 8 chips per side (16 total). The packaging of the bars are identical.
The strip 16 chips work perfectly without any problems.
The 8 bulleted strip recognized in the bios is "planting" Windows 7 at startup (blue screen with the message). I sent the bar for an exchange, hoping to receive 16 chips, but unfortunately I received a Bar to 8 chips that after positioning is still "grow" Windows 7. I decided to return it for a refund. These bars were planned to replace 2 bars of 2 GB to 16 chips. I have a Samsung R540 laptop js01fr.
A look at the picture on the Amazon website it is a bar to 16 chips (8x2), but the risk that one gets to be different ...