For a casual user, you absolutely shouldn’t be doing something that could cause compatability issues, and very easily as well. With how RAM timing operates, it’s a bet that leads to reduced performance usually, best case is one RAM module works slower, and worst case is they’re straight up not able to work together.
Balancing the system is also important in this case as again, having 16GB now or leaving the option to upgrade in the future would throw off the budget as well, so it’s much more likely to be a waste of money than not. Also, as for having tabs in the background, paused videos and whatever else in the background, I find that 8GB is plenty enough for even heavy multitasking. Even when skyping, downloading via Steam and Chome simulataneously, as well as having tabs in the background, the bottleneck is going to be CPU resources and internet speed as opposed to anything else. Spoken from experience here, 8GB on the rig I’m currently using and I’ve never had it buckle under any load so far.
I will concede that some things may benefit form having more, but my point is that it’s such a tiny use case scenario, that it makes more sense to not bother until it’s actually necessary.
Also, I’m glad we can agree on something, and if it were a year or two ago I would actually agree with you, as doing a complete rebuild is a pain. This case however, I personally believe that by the time he’ll find that he needs 16GB or even wants it, it’ll likely be time for a new CPU and motherboard anyway, and at that point, going 16GB makes sense. And no worries about the whole SSD thing, reading through blocks of forum text makes it easy to miss things, and while hitting the page file with several gigabytes would be pretty unpleasant, I can’t think of a situation where that would occur for a gaming build. If this were a video editing station, I’d agree 100% on getting 16GB, I guess that’s something for the OP to keep in mind as well, if he wants to try that in the future.
And the whole no mix-matching thing mainly comes from how doing so means overclocks can be unstable, as well as mess with the timings of the RAM itself, leading to lesser performance or incompatability. The big issue is how the BIOS handles the changing of the timing on the RAM, as some like to set the timings to the faster module CAS-wise, so that leads to instability and the overclock issue.
That said, overclocking isn’t an issue here since it isn’t a K-series, and the problem with a thing like this is that it’s a case-by-case basis. Some people, like you and many others, swear up and down that there are no issues with plenty of evidence, both anecdotal and with proof that nothing goes wrong, while others point out with equal proof what happens when they do it.
Guess this is something for LTT to cover or something, it’s just something that I never personally recommend because the possibility of running into an issue that the user has no idea how to fix, is something that I don’t like risking, even if the chance is pretty small in itself.
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