I've upgraded my iMac's memory/RAM but...

Hello...

Today I've upgraded my 27" QC 3.1 Ghz 2011 iMac's RAM from 4gb to 8GB.
Until now I didn't have any problem.
I also didn't use any video, music or photo editing program yet.

My question is:
Physically old and new RAMs don't look like each other but I can note that specification has changed from 4GB to 8GB in "About This Mac".
Existing RAMs are: On the left darker ones...
Samsung M471B5673FH0-CH9 1048 2GB 2RX8 PC3 - 10600S-09-10-F2
Newly added RAMs are: On the right lighter ones...
Samsung M471B5773DH0-CH9 1108 and 1113 2GB 1RX8 PC3 - 10600S-09-11-B2

What do you think, do they work fine together?
Will I have any performance problem or oppositely get any benefit at my video/photo/music editing works?

Thanks for your answers.

No answer in these 1000s of Steve Jobs?

Qwaf said:

It should be fine as long as you're matching each pair or RAM sticks in the same pair of DIMM slots, just so you're not getting any problems with the whole dual channel memory business.

Click to expand...

Thanks Qwaf...

Is it corretct matching of placing on the photo?
or
Old ones upper line and new ones bottom line? ( or the other way around)

Thanks a lot for the answers.

As I said old and new RAMs physically don't look like each other.
http://www.samsung.com/global/business/semiconductor/productList.do?fmly_id=694&xFmly_id=690
Here is the difference in Component Composition section.
Old (128Mx8)x16 (Original RAMs came with the iMac)
New (256Mx8)x8 (Newly bought RAMs).

I hope this difference is "just ok" as you answered.

Thanks again...