Single Stick drawbacks? how bad are they?

[davelakecity]

DDR2 seems to have jumped alot in price.. Could swear I saw 2x1gig kits a month ago for around $150... now $200 min (???) Messes up my budget so I need a work around.

My real question is:
If I buy only one 1gig stick of ddr2 for my new system how bad will it effect performance (being single channel) compared to two sticks of 512 in dual channel?
also- if i did go 2x512 now... any problem putting in another 2x1gig later on (for a total of 3gig)? No problem having different sizes in different banks 512,512,1gig,1gig etc?

Notes:
The reason for this is that I want to buy another one gig stick later on when I can afford it + when price comes down *maybe.
If I buy two sticks of 512 I can run in dual channel NOW, but it only leaves 2 empty mem slots for future upgrades.
Ideally I'd like to have 2gigs ddr2 (2x1gig) now and buy another pair down the road.
Not planning to OC this system.
Planning to use e6300 cpu or maybe 805d to save money- upgrade later.
Thinking at least 667 pc2-5400 speed for ram in case upgrade to quad core down the road (333fsb)

 

[davelakecity]

http://forumz.tomshardware.com/hardware/sticks-conroe-ftopict201370.html

interesting post - kinda relates to my question...

 

[AddictiveHerring]

lol, I like the Dell explanation, even though I hate the company, singly channel is like a two lane highway, and dual channel is like a 4 channel highway. Sooo it can be about half as slow, honestly dual channel is the way to go, a good interleave kicks ass, 2 512's is better than 1 gig stick. But it also depends on the fsb:memory ratio

I would buy just plain wait and buy a matched pair of gig sticks, or if you must have ddr 2 now, I would buy 2 512's and try to sell them to a friend or something and just stick to the 2X1 gig, adding 2X1 gig plus 2X512 would just confuse things I think. When you switch to a 64 bit os, you can add more mathcing pairs of whatever sizes, because having over 2 gigs in 32 bit xp seems like a huge waste.