Is there a difference in performance? Dual channel vrs Quad channel?

Much the same as the speed of traffic flow between a 2 lane highway and a four lane one...;)

More specifically, at present it's the difference between a nearly empty two lane highway, and a nearly empty four lane highway.  You're still doing the speed limit anyway.  Even the biggest memory hogs in gaming aren't touching it.

 

Going forward, if people actually start making software to utilize the hardware, it will make a big difference.  Benchmarking shows available bandwidth takes a huge dive when you use dual channel, it's not quite half speed, but close.  Benchmarking also shows it does absolutely dick for the vast majority of software, actually costs marginal performance in many applications.  The reason is very few applications even approach the bandwidth limitations of dual channel DDR3 and DDR4.  Once you break those limits, the capability will pay off in spades.

Ah ..bandwidth... ok, I get it. Thanks both of you. Quad it is. 

For the most part this is true until you take into account virtual memory. Windows does this. In order to keep things from crashing all your memory has to run at the same speed. Unless you have an ssd your virtual memory slows down the system. 

Admiral, I will likely have 32 gigs of DDR4 Quad channel and an M.2 SSD like the Samsung 860. 

I was wondering this recently too as AMD Ryzen is only 2 channel I believe. But from the little I have heard about it for most user cases there will be very little difference in it. What Psychoak says above seems to echo what I have come across.

Skylake is also 2 channel.  The maximum memory bandwidth on an i7 6700k is 34.1GB/s, DDR4-3200 is only capable of 25.6GB/s.

 

Unless you can use more than two thirds of the bandwidth the processor is capable of handling, you can't achieve this with most tasks to begin with.  Things like video encoding, compiling.  You can handily outperform the Skylake architecture with different architectures on certain tasks because of that limitation, but it's a very select few tasks for the typical gamer.  If AMD is concerned with competing against Skylake, a high bandwidth application isn't going to matter much even in the rare instances where it would matter.

 

 

This is only true when a program is utilizing that virtual memory alongside your RAM.  If it is, you have massively less RAM than you need.  Buy enough RAM that you never need virtual memory, or go back to the 90's where your computer belongs.

 

SSD's aren't fast either, so little to no help there.  Assuming you meant the 960, the pro is still only 3500MB/s sequential read, as opposed to the above stated 25.6GB/s.  They may be an order of magnitude faster than disk drives, but they're still an order of magnitude slower than RAM.  If your processor is every trying to work off the drive, it's going to have performance more in line with your phone than a modern desktop.

correct^ it will run dual channel, but you can still plant 32gigs onto those two slots but it is in most cases pointless.
Unless one has a "massive" project file to render or work on, nobody will ever need 32gigs meaning that you will need that amount to minimize rendering 4K videos for example 64 Gigs was the max some years ago that programms were able to utilize. Not up to date if this meanwhile changed but hey you could meanwhile get 128gigs lol.
Anyways... just a quick video about dual vs quad channel

I haven't actually used 32 yet, but I've used a lot more than 16.  That's a Bill Gates worthy statement, it will probably only be a few years before software has bloated to the point where 32 is a minimal approach to gaming.

 

If you run multiple VM's for work, you can hit 32 real fast.

NQR.

My current usage is 73% of 32 gig.  Multiple instances of a 2D graphics proggy can do that VERY easily.  Q simple 32bit PSP 6, would you believe.

I've instances of being over 90% so it's quite arguable that I'd be better off with more than 32.

It's not a toy PC spec...so actually gets used.....and even this amount of ram usage is without any VMs running...which naturally demands even more.

Comp specs re ram...

ASUS X99 Deluxe LGA2011v3 MotherBoard

Intel i7 5960x 3.00Ghz @3.50Ghz LGA2011v3 CPU

32G Corsair Dominator Platinum [4x8G] 2666MHz DDR4 Ram

 

To add another 32 I'd also have to change the Noctua cooler...as it's a big bugger and in the way of the 'secondary' slots.

@Jafo but you're not an average "player"
Well content creators, for those that run VM´s to pick apart stuff, or like you design high res textures for games, or those that do Premiere, AE. It can be usefull but as a normal guy playing a game now and then and surf the www they will not need those 32gigs 16 is more than enough even if you have mutiple instances of progs running at the same time.
What i mean is unless you are one of those players that owns a RED Camera and you have to reneder out the footage or stuff that Jafo does you will not exeed the 16GB.

I render stuff myself and also do §D 16 gigs wont be exeeded here.

Have to admit that i have a rig that runs a VE and nothing else
>Dont do anything like that on this puppy.
 

 
The Block of awesomness (NHD14)  - you shall NOT pass! 

I broke 16 without that stuff, I was beta testing GC3 with messengers, web browser, etc, and doing other stuff between turns. :)  It was burning through 12 or so on it's own at the time, I'm sitting at 4.9 here with just the browser above my normal always on stuff, the biggest hog of which is slack at ~230MB between six executables presently.

How'd you guess? ...;)