Question RAM detected differently through 3 different apps?

[fuschited]

Hi there, so I initially had 4GB (2x2), then just 2 days ago I added another 4GB (2x2) of the same make and model RAM with the same speeds. So, Windows detects 8.0GB of Installed RAM but only 4GB of Useable. I thought this was concerning as my new sticks weren't working. I checked BIOS and it was detected as 8GB. I tried CPU-Z just for another view, and it detects 8GB but running at SINGLE channel although I have 4 sticks installed.

Can anyone help?

 

[Third-Eye]

Hi there, so I initially had 4GB (2x2), then just 2 days ago I added another 4GB (2x2) of the same make and model RAM with the same speeds. So, Windows detects 8.0GB of Installed RAM but only 4GB of Useable. I thought this was concerning as my new sticks weren't working. I checked BIOS and it was detected as 8GB. I tried CPU-Z just for another view, and it detects 8GB but running at SINGLE channel although I have 4 sticks installed.

Can anyone help?

Please post system specs including motherboard model number.