Yes, I'd say if it's not on the certified list of 2x compatible DVD-R's, then you're probably talking 1x. Get a Pioneer, Apple ,TDK or other 2x disc and see how long it takes to burn a full DVD. If it burns at 2x, then that other stuff you're buying isn't true 2x. If it still doesn't burn at 2x, you've got system issues to troubleshoot.