Is faster DDR3 RAM more important with AMD CPUs?

h3r3t1k

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I thought I was gonna use el cheapo G1840 for a budget build but decided to spend a little more to get a X4 845 on a FM2+ mobo. I've already bought the 1333MHz CL9 kit which is the fastest the G1840 supports and which should work fine with the X4 845 which supports 2133MHz. Where I live the slow kit cost 32 bucks. After I checked prices of 2133MHz kits of the same size I realized that 2400MHz kits can be had cheaper. I found a Corsair Vengeance 2400MHz CL11 kit for 39 bucks so only 7 bucks more. I'm guessing I should get this and return the other kit? My motherboard supports up to 2400MHz.
 
The FM2 platform supports the higher memory speeds better then lower end intel does.
Now FM2 also has to squeeze every drop of extra performance it can get because after you have the best FM2 cpu (now the 845) then you have to overclock and run high speed memory to almost but not really get core i3 level performance.

Wish you would have asked for advice early and would have told you to get the 1840. Its not a great CPU but at least you will have an upgrade path. With the x4 845 you are maxed out at sub-i3 level performance and will need a new mobo, cpu, (memory if you go skylake), and windows license in order to upgrade.
 

h3r3t1k

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Isn't the top tier CPU the 880K? I have no plans to upgrade because I will not make the jump to anything higher than 1080p and the X4 845 will not bottleneck any 1080p card. Newer games tend to require 4 threads which the G1840 doesn't have. In it's price class the X4 845 is pretty amazing. You didn't answer my question btw.
 


If you aren't using an integrated gpu then memory speeds don't matter at all. However the athlon x4 845 will bottleneck every card that is above gtx 950 / r9 270x performance due to its weak single core performance. If you start noticing low fps in mordern games and have a good gpu that will be the problem. For now it will be fine.
 
Yes, my mistake, the 845 is not the top in FM2 cpus. My brain just zoned out on that one.

Your statement about the 845 not bottlenecking a 1080p is incorrect. Even a GTX-960 or R9-380 will be held back by an fm2 cpu.

In regards to your initial question, the speed improvement of faster ram is very notable in FM2 APUs where the GPU is using system memory and thus the higher bandwidth ram makes a noticeable improvement in GPU performance. Now with an x4 CPU you still notice some marginal gains due to the fact that the CPU is going to be maxed out playing any game. Intel systems on the other hand will see little to no improvement when gaming, mostly because with intel the igpu is not sufficient for gaming and thus a dedicated gpu is a must.
 

h3r3t1k

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For anyone building a budget conscious mid-range possible gaming system with a discrete graphics card, the Athlon X4 880K processor from AMD offers some nice value. Under the hood this is essentially a 100 MHz faster version of the A10-7870K which we reviewed, but as it does not have integrated graphics this allows all the power budget to be put squarely onto the overclockable CPU. Pairing it with a mid-range graphics card, such as the R9 370 or GTX 960 for around $200, makes a system easily capable of high-end graphics consistency on eSports titles and mid-range quality settings at 1080p for the major titles of the year.
http://www.anandtech.com/show/9793/best-cpus

I don't know where you got your info regarding bottlenecks from but Anandtech is one of if not the most reputable hardware site out there. They wouldn't recommend pairing it with a GTX 960 if it was bottlenecking it. X4 845 is basically equivalent to 860k and 880k is a little faster.