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Mixing and matching RAM

Joined
Jul 7, 2010
Messages
350
Motherboard
GA-P55A-UD4P
CPU
i7-860
Graphics
5870
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  2. Mac mini
  3. Mac Pro
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  1. iOS
I have two 8 GB chips with the following specs:

  • DDR4 3200 (PC4 25600)
  • Timing 16-18-18-36
  • CAS Latency 16
  • Voltage 1.35V
I need to add two more 8 GB chips but I am not sure if they need to meet these specifications precisely. It's easy finding DDR4 3200/1.35V chips, but do the timing and CAS need to match the old chip specs, too?
 
Joined
Nov 4, 2011
Messages
663
Motherboard
Gigabyte GA-Z170X-UD3 F23g
CPU
i7-6700K
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RX 580
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  1. iMac
No @Connie Mac provided you set the ram in your bios manually to the lowest common denominator of the memory sticks you wish to deploy.

Greetings Henties
 
Joined
May 29, 2012
Messages
466
Motherboard
Gigabyte Z390 Gaming X
CPU
i9-9900K
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Vega 56
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I've tried this before on the Z390 Gaming X, and I think it varies with the pairs of RAM. I couldn't get it to work. They recommend buying a package of RAM, so if you wanted 32 GB, you would buy a pack of 4 x 8 GB. There are people who say that the 4 are tested to work together.

The way I did it was to first buy one pair, and when I found that it didn't work with my old pair, I purchased another set of the new pair. They ended up working fine, but there was some problems when I upgraded to the latest BIOS. It didn't let me run it in the Turbo mode. I had to rollback to the older BIOS and now it is working fine again.
 
Joined
Jul 7, 2010
Messages
350
Motherboard
GA-P55A-UD4P
CPU
i7-860
Graphics
5870
Mac
  1. MacBook Pro
  2. Mac mini
  3. Mac Pro
Mobile Phone
  1. iOS
OK, thanks for the tips. I found another set of chips that had the same specs and they seem to be working fine. I also did an i5-9400 to i9-9900 update, so the computer is running at top speed, I think!
 
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