hi all, i've an old mobo mercury with 845GL chipset which supports only ddr266. i've a ddr266 256MB module, want to add another 512MB but cannot find ddr266 anywhere. so i was wondering whether i could add ddr400 and use it along with ddt266. i heard a shopkeeper say ddr400 won't run on ddr266. will this give any problems. does this depend on the brand of ram? if i'm correct ddr400 runs at same voltage as ddr266, so what speed will both run at? will i have any problems with restarts or anything? Please someone confirm that they will run fine together even if they're of different brand. Thanks in advance.