It's pretty close to linear, yeah. Figure the hibernation process basically writes the entire contents of RAM to the HDD. Logically, the write process would double if you doubled your RAM or quadruple if you quadrupled your RAM.
I run 512MB and both hibernate and resume are pretty quick with a 7200rpm desktop HDD, a matter of a few seconds.
I'm also running older hardware than you, as well.
Have you looked in the FAQ yet?
How about the Wiki?
Under normal circumstances, a signature would go here.
It's only linear during the loading bar section during resume (that's when the hard drive is being dumped back to ram), so you might double that time.
But your POST and the time it takes from the finish of the loading bar to when you are actually up and running is still the same. So overall when you sum up all the times, there wont necessarily be a linear correlation in overall resume time as a function of ram size.
when i last time opened my system, i upgraded from 512MB to 1G, and i think the times of wake up from / go to hibernation is nearly the same... i think windows dumps only the used megabytes, not the whole, so if the system is not fully loaded, there will be no huge difference...
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