upgrading from 512x2 to 2g or 1.5g with mixed ram types

ok so i have 2 computers both have the same motherboard gigabyte GA-7N400 pro2 i had 1 gig (512x2) of twinx1024-3200llpt in both computers. my plan was to upgrade one of them to 2 gig and leave the other at 1g for the time being so i bought 1g (512x2) of twinx1024-3200c2pt installed it and when i boot it tells me i only have 1g , i read through the manual for my mb and low and behold despite having 4 slots i can only have max of 6 sides so 3 dimms of double sided , or 2 dims of double sided and 2 dims of single sided , i was about to send the ram back with the intention of buying a single 1g stick to get me to 2g but before being stupid and wasting my time and mony on restocking fees i thought i would read this board , i read lot of people asking about ways to upgrade to 2g from 1g(512x2) and the theme i keep seeing is throw away what you have and buy 2g(1gx2) , i also read that i cant mix a single 1g stick with my 512x2 so im a bit stuck , i payed around 300 bucks for the ram in each comp i have now so i dont really want to throw it away and spend 250 bucks for ram that is already outdated just to boost performance on one of my comps

so with a little thinking i thought i would try something , i took 1 stick of the 3200llpt from my main comp and put it in my second comp so i have 1.5 in that one all 3200llpt , i then took the 2x512 i just bought and put it in this comp and moved the single 512 stick to dimm 2 both comps boot ok , and they both say they recognize 1.5 gig , but i havent played any games on em yet to see if i notice any performance differance and i havent run them long to see if they are stable , my question is this.... is what i did ok? can you split the matched pairs like that , and in this main comp where i have mixed the c2pt with the llpt is that ok where there are slight differences in latencys , i looked all over but i dont think the llpt is being made anymore so i got the c2pt because it seemed to be the best and closest to what i already had , i want to get your opinions before i leave em like this for too long not knowing if what i did is actualy working properly

if what i did isnt proper then what are my options fur upgrading

PS i have a new board on the way (gigabyte ga-k8u-939) as im planing to upgrade my main comp to a socket 939 amd athelon 64 3700+ san diego , this board also has 4 dimms but im thinking there the same setup as the board i have now where i can only have a max of 6 sides , i had planed on just puting 1g ddr400 ram in this one for the time till i can afford to buy some new ddr2 or whatever with a new board later down the road once prices come down some

sorry if i seem a bit ignorant i have built my own comps but i definately dont know everything there is to know about everything latencys is one of the things im not too knowledgable about