That's completely wrong. You only have to have sticks with identical sizes, speeds and timings (source
Even Intel's original white paper on dual channel memory in 2003
(it's on page 8) states:
"For the best dual-channel memory performance on motherboards with the Intel dualchannel DDR chipsets, you must use identically paired memory modules...
In this context, “matching” modules means:
1. Both modules are the same capacity (e.g. both are 256MB, or 512MB)
2. Both modules are the same speed (e.g. both are PC2700 or PC3200)
3. Both have the same number of chips and module sides (e.g. both have the
same number of chips on the module, and both are either single-sided or
As long as you do your research and pick sticks carefully, you'll be fine.
All the dual/triple channel kits are is sticks that have been paired and designed to work perfectly together. You can make you own kits, but it's usually more expensive and might require tweaks. That doesn't mean it won't work.