Question Red motherboard lights turned on at boot, system still starts but is very slow ?

[Dalamajama]

I'm trying to get an old system up and running; at first the cpu and ram LEDs turned red and the system wouldn't turn on. I took everything out of the case and put it on an acrylic panel and now the cpu and ram LEDs still turn red (along with the boot device LED), but the system now boots. However, it's very slow with cpu and disk utilization basically pinned at 100% whenever anything happens. All the components are detected normally, and everything seems to be functional.

I'm a bit confused as to how several of the indicator LEDs could be red but the system is still functional. Does anyone have an idea what might be happening here?

Motherboard: Asus Z170A
CPU: Core i5-6500
Ram: 16 GB Kingston

 

[RARRAF]

I would take a wild guess maybe the cmos battery on the motherboard is dead and needs replacing it's a watch battery easy to clip out and replace only £2 to £3 try that first.