Question Will there be any performance degradation having different size memory sticks in my pc?

AbhiRockz

Honorable
Aug 4, 2014
113
0
10,690
1
I actually have two 8GB ram sticks, and two 16GB ram stick, I know that different ram modules disable dual-channel which degrades performance. Can someone clarify these a bit for my configuration.

Here are my memory configuration details,

Do I have to switch immediately to a 16GB ram sticks to avoid performance issues?

Code:
sudo lshw -c memory
  *-memory
       description: System Memory
       physical id: e
       slot: System board or motherboard
       size: 48GiB
     *-bank:0
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-16GTZR
          vendor: Fujitsu
          physical id: 0
          serial: 00000000
          slot: ChannelA-DIMM0
          size: 16GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:1
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-8GTZRX
          vendor: Fujitsu
          physical id: 1
          serial: 00000000
          slot: ChannelA-DIMM1
          size: 8GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:2
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-8GTZRX
          vendor: Fujitsu
          physical id: 2
          serial: 00000000
          slot: ChannelB-DIMM0
          size: 8GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:3
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-16GTZR
          vendor: Fujitsu
          physical id: 3
          serial: 00000000
          slot: ChannelB-DIMM1
          size: 16GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)

Motherboard Details:


Code:
# dmidecode 3.2
Getting SMBIOS data from sysfs.
SMBIOS 3.2.0 present.

Handle 0x0002, DMI type 2, 15 bytes
Base Board Information
    Manufacturer: ASRock
    Product Name: Z490 PG Velocita
    Version:                       
    Serial Number: M80-D7030500495
    Asset Tag:                       
    Features:
        Board is a hosting board
        Board is replaceable
    Location In Chassis:                       
    Chassis Handle: 0x0003
    Type: Motherboard
    Contained Object Handles: 0
 

Lutfij

Titan
Moderator
When dealing with ram, look at them as you when buying a pair of shoes after you loose one shoe out of a pair at the beach. Even though you might yet have one shoe out of the old pair, the person at the store will not sell you one shoe, rather a pair. For your case, you're advised to buy a matched set of rams or kits as they are referred to. Since you own a 32GB ram kit and a 16GB ram kit, resorting to the 32GB would be worthwhile. If you intend to increase your ram, pick the same 32GB kit as you have now. if you can't source the same kit, you can ditch the two kits and pick out 2(2x16GB) kits.
 

AbhiRockz

Honorable
Aug 4, 2014
113
0
10,690
1
When dealing with ram, look at them as you when buying a pair of shoes after you loose one shoe out of a pair at the beach. Even though you might yet have one shoe out of the old pair, the person at the store will not sell you one shoe, rather a pair. For your case, you're advised to buy a matched set of rams or kits as they are referred to. Since you own a 32GB ram kit and a 16GB ram kit, resorting to the 32GB would be worthwhile. If you intend to increase your ram, pick the same 32GB kit as you have now. if you can't source the same kit, you can ditch the two kits and pick out 2(2x16GB) kits.
So does this configuration of mine (motherboard and memory sticks) causes any noticeable performance degradation? "Since you own a 32GB ram kit and a 16GB ram kit", I currently have 8GB pair and 16GB pair.

From my mother board documentation I found this below sentence,

For dual channel configuration, you always need to install identical (the same brand, speed, size and chip-type) DDR4 DIMM pairs.

So, currently bank0, bank 1 have 16gb and 8GB. So if I set,

bank 0 - 16GB
bank1 - 16GB
bank2 - 8GB
bank3 - 8GB

Will that be enough for now.
 
Last edited:

k1114

Titan
Moderator
You should still be in dual channel as long as the ram is in the right slots which results in no change in performance from different size sticks. You can confirm in bios or cpuz. It should be 16 - 8 - 16 - 8. Each channel would have 24 gbs and be able to pair each stick which is why it's still dual channel.
 

AbhiRockz

Honorable
Aug 4, 2014
113
0
10,690
1
You should still be in dual channel as long as the ram is in the right slots which results in no change in performance from different size sticks. You can confirm in bios or cpuz. It should be 16 - 8 - 16 - 8. Each channel would have 24 gbs and be able to pair each stick which is why it's still dual channel.
If you see this https://www.tpstech.in/products/asrock-z490-pg-veloctita-lga1200-atx-motherboard-with-pcie-4-0-thunderbolt-3-and-multi-gpu-support, that is my motherboard. There is no color coding for memory slots, all of them are black.

How to check if I have inserted in correct slots?

This is how I have them now,

ChannelA-DIMM0 - 16GB
ChannelA-DIMM1 - 8GB
ChannelB-DIMM0 - 16GB
ChannelB-DIMM1 - 8GB

Should I change it to,

Bank 0 slot: ChannelA-DIMM0 16GB
Bank 1 slot: ChannelA-DIMM1 16GB
Bank 2 slot: ChannelB-DIMM0 8GB
Bank 3 slot: ChannelB-DIMM1 8GB


Code:
  *-memory
       description: System Memory
       physical id: e
       slot: System board or motherboard
       size: 48GiB
     *-bank:0
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-16GTZR
          vendor: Fujitsu
          physical id: 0
          serial: 00000000
          slot: ChannelA-DIMM0
          size: 16GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:1
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-8GTZRX
          vendor: Fujitsu
          physical id: 1
          serial: 00000000
          slot: ChannelA-DIMM1
          size: 8GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:2
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-8GTZRX
          vendor: Fujitsu
          physical id: 2
          serial: 00000000
          slot: ChannelB-DIMM0
          size: 8GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
     *-bank:3
          description: DIMM DDR4 Synchronous 3600 MHz (0.3 ns)
          product: F4-3600C18-16GTZR
          vendor: Fujitsu
          physical id: 3
          serial: 00000000
          slot: ChannelB-DIMM1
          size: 16GiB
          width: 64 bits
          clock: 3600MHz (0.3ns)
 

ASK THE COMMUNITY