How important is matching RAM speed?

[SleepyFool]

I currently have dual channel RAM, with a 4 GB 1333 mhz stick in two slots, and two slots free. I want to upgrade with two more 4 GB sticks, but I'm torn between http://www.amazon.com/Kingston-Technology-1333MHz-KHX1333C9D3B1K2-8G/dp/B004DDI0IE/ref=sr_1_6?s=electronics&ie=UTF8&qid=undefined&sr=1-6&keywords=10600+8gb+ram at a flat 1333 mhz, or going with http://www.amazon.com/dp/B00J8E912M with automatic overclocking up to 1866 mhz.

The price difference isn't a major concern. I'm looking for the option which will give me greater performance.

And if it isn't too much trouble, while I want an answer to this specific question, I'd love to know the why and how.

Thanks!

 

[markwp]

Unless you exactly match your existing ram, your system will default to the slowest stick in your rig. Mixing and matching will work for capacity, but at a cost of real benefit. IMO, since price difference isn't a major concern, you would be better off replacing the existing ram with a 2x8 setup if 16g is your goal. As far as speed goes, just be sure your m/b supports the speed and brand your buying. Generally, most name brands will work as advertised on most boards, but the speeds can vary depending on the age of your board.

Mark

 

[Tradesman1]

The two you show are both 1333 sets and that's it....the second set the Fury's, have opted away from the standard of using XMP profiles and depend on compatibility for PnP to 'overclock' to their designated freq, in this case on a supported mobo say if the default was 1066 for the mobo, they would OC themselves to 1333 (if you want sticks that will OC to 1866 you need to get the 1866 set.

As far as mixing with your currrent sticks, there's no guarantees two sets will play together, even if you get two sets of the same exact model (sticks in a set are tested to play together, which is why a 4 stick set often costs more than getting a pair of 2 sticks sets - it takes more testing to find 4 that all play nice than to find 2. It's also why the manufacturers only guarantee by the packaged set, they don't guarantee two sets together.

SO the question here would be will 8 GB suffice - if so suggest getting a 2x4GB set and then if the old sticks will play - it's a bonus...else if you NEED more than 8 GB look to a 2x8GB set (if your mobo supports that, if not a 4x4GB set for guaranteed DRAM)

 

[SleepyFool]

Well, the $25 difference isn't a concern, but the hundred dollar difference in getting a brand new 16 GBs from scratch would be. I just want to add to what I have to go from 8 GB to 16 GB total. I guess it doesn't really make a difference which set I use to get there. I'll just throw them into the other channel and see how it goes.

 

[Tradesman1]

If you have any problems, give me a shout, can often get them to play via voltage/timing adjustments, DRAM is sort of a specialty of mine

 

[SleepyFool]

Things have been working well, overall... programs open faster, I can have browser tabs open like never before... but what's weird is, starting up from a full shutdown state seems to fail sometimes, and nothing initializes, and I have to restart the computer to get it to boot up. Like, nothing happens, the screen registers a signal but just stays black. The RAM is registering just fine in HWInfo, I'm seeing a noticable performance increase, I just... am having that odd startup issue now.