Question Why does my Mobo detect both RAM sticks but only uses one of them

[Litro_301]

specs:
CPU: Intel i7-4790
MOBO: ASUS B85M-G
RAM 2x4gb ddr3 1600MHz HyperX Fury
GPU: MSI Ventus RTX 2060
Userbenchmark: https://www.userbenchmark.com/UserRun/37599554
my problem is that my motherboard only use one stick of RAM
what i've tried so far:

• Reseated both sticks alone and in pairs in all of the slots
• Checked andvanced options for systemboat through msconfig (which says maximum memory is 4gb)
• Tried using older and slower (1333MHz) ddr3 ram sticks, and got the exact same result were the computer would detect the full amount of ram but only use one stick.

so both sticks works well on their own in every slot on the motherboard. The PC detects both sticks in the bios menu aswell in the taskmanager. But when i plug in both RAM sticks the bios detects them being in the correct sockets and with the correct amount and speed the same in taskmanager. But in taskmanager it says that only 3.5 gb are usable.
Thanks in advance for reading this and helping me.

 

[CountMike]

specs:
CPU: Intel i7-4790
MOBO: ASUS B85M-G
RAM 2x4gb ddr3 1600MHz HyperX Fury
GPU: MSI Ventus RTX 2060
Userbenchmark: https://www.userbenchmark.com/UserRun/37599554
my problem is that my motherboard only use one stick of RAM
what i've tried so far:

• Reseated both sticks alone and in pairs in all of the slots
• Checked andvanced options for systemboat through msconfig (which says maximum memory is 4gb)
• Tried using older and slower (1333MHz) ddr3 ram sticks, and got the exact same result were the computer would detect the full amount of ram but only use one stick.

so both sticks works well on their own in every slot on the motherboard. The PC detects both sticks in the bios menu aswell in the taskmanager. But when i plug in both RAM sticks the bios detects them being in the correct sockets and with the correct amount and speed the same in taskmanager. But in taskmanager it says that only 3.5 gb are usable.
Thanks in advance for reading this and helping me.

What does CPU-Z say ? Check both tabs, SPD and memory.

 

[Litro_301]

specs:
CPU: Intel i7-4790
MOBO: ASUS B85M-G
RAM 2x4gb ddr3 1600MHz HyperX Fury
GPU: MSI Ventus RTX 2060
Userbenchmark: https://www.userbenchmark.com/UserRun/37599554
my problem is that my motherboard only use one stick of RAM
what i've tried so far:

• Reseated both sticks alone and in pairs in all of the slots
• Checked andvanced options for systemboat through msconfig (which says maximum memory is 4gb)
• Tried using older and slower (1333MHz) ddr3 ram sticks, and got the exact same result were the computer would detect the full amount of ram but only use one stick.

so both sticks works well on their own in every slot on the motherboard. The PC detects both sticks in the bios menu aswell in the taskmanager. But when i plug in both RAM sticks the bios detects them being in the correct sockets and with the correct amount and speed the same in taskmanager. But in taskmanager it says that only 3.5 gb are usable.
Thanks in advance for reading this and helping me.

What does CPU-Z say ? Check both tabs, SPD and memory.

in the Memory tab it says that my size is 8 gb which is true and that i use ddr3 which is also true but. It also says that i have DRAM frequency of 789.1 MHz which is half of what i have (1600 MHz)
in the SPD tab it recognize both ram sticks in the correct slots with the same size. But the frequency under "JEDEC" is at it max 800 MHz and at it's lowest 640 MHz on both sticks. And under the Max Bandwith it also says "PC3-12800J (800 MHz)

 

[CountMike]

in the Memory tab it says that my size is 8 gb which is true and that i use ddr3 which is also true but. It also says that i have DRAM frequency of 789.1 MHz which is half of what i have (1600 MHz)
in the SPD tab it recognize both ram sticks in the correct slots with the same size. But the frequency under "JEDEC" is at it max 800 MHz and at it's lowest 640 MHz on both sticks. And under the Max Bandwith it also says "PC3-12800J (800 MHz)

That's DDR memory and programs display only half of operational speed so any of those numbers should be multiplied by 2.
Difference 789.1 MHz and 800MHz is due to uneven frequency of FSB.

 

[Litro_301]

That's DDR memory and programs display only half of operational speed so any of those numbers should be multiplied by 2.
Difference 789.1 MHz and 800MHz is due to uneven frequency of FSB.

ok thanks for the information. Do you know what else could cause this problem or is it likely that the MOBO i permamently damaged? Should i maybe try to increase the voltage via bios.

 

[CountMike]

ok thanks for the information. Do you know what else could cause this problem or is it likely that the MOBO i permamently damaged? Should i maybe try to increase the voltage via bios.

If memory is correctly recognized by BIOS and programs, than it's likely something with your windows. Some more things to check, in CPU-Z does it show dual or single channel ?

 

[Litro_301]

If memory is correctly recognized by BIOS and programs, than it's likely something with your windows. Some more things to check, in CPU-Z does it show dual or single channel ?

under the Memory tab in CPU-Z it says dual channel.
thanks for the help btw.