4gb dual channel vs 5gb single channel ddr3 ram

[new boy]

hi people

i wish to upgrade a 2nd hand laptop i purchased on a popular internet auction site. currently it has a i5-520m but only 2gb of ddr3 ram

assuming its a 2 x 1gb kit, do you think i should just take out 1 of them and slot in a 4gb stick, for total of 5gb, or will i loose a considerible amount of speed from not having duel channel.

would i be better of just getting a 2 x 2gb kit and taking out all on the 1gb.

so to summerise;
1gb + 4gb for 5gb no dual channel?
or 2gb + 2gb for 4gb with dual channel?

any thoughts???

thanks.

[Sputnik]

I would try and check what the board can handle, Some boards have limits on the size of sticks you can use. My preference would be the 2x2 keeping dual channel.

[new boy]

8gb 2 x 4gb is the max

[kalniel]

2x2gb - it's easier on the memory controller.

[Pob255]

I'd also check which version of windows you have, not worth putting 5gb into a 32bit OS

[new boy]

I'd also check which version of windows you have, not worth putting 5gb into a 32bit OS

very true

ok, 2 x 2gb it is.

perhaps i can get a bit of money back from the 1gb sticks too.