Dual channel problem

hoangvietha · February 7, 2023

Hi. Just bought a pair of 2x8GB RAM stick. Installed on A2 and B2 slot but windows 10 and BIOS read as 16GB but only 8GB utilized. When I installed it on A2 and B1 slot it work normally. And another problem is that when I enable XMP with both installed way it refused to work and pc boot and reboot 3 times before it return to stock speed at 2133mhz. Tried everything included update Bios to latest.

My pc specs:

Ryzen 7 1700

Apacer Nox 2x8GB Ram

Asrock B450m pro f bios ver 7.4

paddy-stone · February 7, 2023

For utilization it should be an easy fix. type in system configuration, go to the [boot] tab, and choose [advanced setup], check the box marked [max memory], if it's already checked, uncheck and re-check it. hit apply, then OK... and you should get notice to reboot IIRC, if not manually reboot and should be fixed now.

For the speed, have you tried setting it manually to the desired speed? also, it may need more voltage... but can't advise on that side of it as I'm not running AMD systems at the moment and can't remember.

YoungBlade · February 7, 2023

What is the speed of the RAM?

First gen Ryzen often had issues with RAM speeds faster than DDR4-3000. Sometimes it could only handle speeds as low as DDR4-2666, which is the rated spec for that generation of chips. So if you have DDR4-3200 or DDR4-3600, it's very possible that your R7 1700 just won't work with the RAM clocked at that speed.

You can try enabling XMP, and then (before leaving the BIOS) manually setting the speed to something lower, like DDR4-2933. That might let you boot.

As for the dual-channel issue, we need to figure out if the slot on the motherboard is the problem. Can it boot correctly with just 1 stick installed in slot B2?

Also, does it work with the RAM installed in A1 and B1? That is also a valid dual-channel config, even if it's not what you're "supposed" to use, according to the manual.

hoangvietha · February 8, 2023

tried everything so far including msconfig, enable XMP and change bus speed manually. Tried both ram stick individually and each work perfectly normal with XMP on