AsRock Z370: Which memory kit to buy?

Shujee

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Oct 24, 2013
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I have purchased AsRock Z370 Killer SLI/AC with i5 8400 and am now confused about RAM.

1. Should I buy 2 x 8GB or 1 x 16GB (or 4 x 4GB?!)?
2. How does that relate to single/dual/quad channels and how does that affect speed?
3. Does my motherboard/processor even support dual/quad channels?

Lastly is there a real-world difference between the performance of 2400 vs 3000 or 3200 speed kits?
 
Solution
1. a 2x8GB
2. dual channel means you have twice more the memory alllocation bandwidth. it wont affect speed that much but it will definitely not make your high-end games not stutter/lag/slow down on high fps rates
3. supports only dual channel
4. no not really. unless if you are doing graphics/video rendering. and not alot of games are RAM intensive. but higher OC frequency can allow you to OC your CPU even at higher speeds at less volts. when choosing a certain specific RAM freq, you always have to look at the price first. sometimes a shop will sell a 2400 and a 3200 at the same price. and of course go for the 3200.

your board states
https://www.asrock.com/MB/Intel/Z370%20Killer%20SLIac/index.asp#Specification
- Dual Channel...

marksavio

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Dec 23, 2017
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1. a 2x8GB
2. dual channel means you have twice more the memory alllocation bandwidth. it wont affect speed that much but it will definitely not make your high-end games not stutter/lag/slow down on high fps rates
3. supports only dual channel
4. no not really. unless if you are doing graphics/video rendering. and not alot of games are RAM intensive. but higher OC frequency can allow you to OC your CPU even at higher speeds at less volts. when choosing a certain specific RAM freq, you always have to look at the price first. sometimes a shop will sell a 2400 and a 3200 at the same price. and of course go for the 3200.

your board states
https://www.asrock.com/MB/Intel/Z370%20Killer%20SLIac/index.asp#Specification
- Dual Channel DDR4 Memory Technology
- 4 x DDR4 DIMM Slots
- Supports DDR4 4266+(OC)* / 4133(OC) / 4000(OC) / 3866(OC) / 3800(OC) / 3733(OC) / 3600(OC) / 3200(OC) / 2933(OC) / 2800(OC) / 2666 / 2400 / 2133 non-ECC, un-buffered memory
- Supports ECC UDIMM memory modules (operate in non-ECC mode)
- Max. capacity of system memory: 64GB**
- Supports Intel® Extreme Memory Profile (XMP) 2.0
- 15μ Gold Contact in DIMM Slots

*8th Gen Intel® CPU supports DDR4 up to 2666.
Please refer to Memory Support List on ASRock's website for more information.

**Due to the operating system limitation, the actual memory size may be less than 4GB for the reservation for system usage under Windows® 32-bit OS. For Windows® 64-bit OS with 64-bit CPU, there is no such limitation.


they also provided you a list of RAMs with the highest compatibility rate
https://www.asrock.com/MB/Intel/Z370%20Killer%20SLIac/index.asp#Memory
 
Solution
Dual channel mobo so 2x8. Slightly faster than a single stick.

There is a framerate difference with faster ram but how much depends on each game. 2666 is the fastest non-overclock ram coffee lake can accept. If 3200 can be found for close price that would be good. Check the mobo QVL for memory that’s guaranteed to work.