8gb ram dual channel vs 12gb ram performance

[simeon15]

I own a HP pavilion n209tx laptop. The hp website states max RAM capacity is 12gb. Currently I have 4gb*2 on both slots. I would like to know if replacing one 4gb with an 8gb stick of same frequency will affect performance? I see that running photoshop+lightroom and adobe Bridge at the same time slows my system down. I understand a better processor would solve the issue but since the memory often requires more RAM, does that mean that the 12gb will improve performance by at least 10-15%? What happens to dual channel? Should I stick to the 8gb?

[porina]

If you really need 12GB of ram and 8GB wont do, just do it. Running low on ram is a worse performance impact than slower ram. Otherwise it is personal choice. You might lose some bandwidth but most apps aren't that sensitive to it anyway.