Does using two different speed 512mb DDR memory sticks at the same time cause any problems? ECS KT-600 motherboard. Getting ready for FSX.Thanks,Dick - Near 5G8

Should not do any harm, but depending on how that ECS deals with RAM.1.they might all run as slowly as or slower than the slowest chip of one of the banks.2.It might not work at all if that ECS tries to clock the slower ones up to the speed of the faster oneNOTE: after installing if the DIMMS work, you can always run memtest a few times to check for stability

'Preparing for FSX' should include a thought about 2GBs of memory IMHO. ;-) Personally, I wouldn't mix RAM but Davis' advise to run memtest in case you do is very good. www.memtest.orgHST, nowadays, it seems best to ALWAYS buy pairs of modules. Single channel platforms are history more or less & selling single modules will be easier now than in the future. Hope this adds to thoughts, good luck and kind regards Jaap