Bought new, faster RAM and my MHz went down. Help

Always good to check for motherboard BIOS upgrades.  Otherwise, you may have to keep your RAM for your next motherboard. :)

I'm not a RAM expert, but memory has several parameters besides raw speed.  It may be that this was the best solution your BIOS found based on the other timing issues.  Check your docs, and also check if you went from 2 to 4 sticks.  That can make a difference to the maximum speed.

@adina35 

One of 2 things: 

1) The motherboard doesn't support faster RAM 

2) BIOS settings or software needs to be changed to support the faster RAM.

Best to check with the company that manufactured the RAM. Faster RAM in MHz doesn't always mean better...

I would suggest using this calculator to compare old RAM to new RAM: 

https://notkyon.moe/ram-latency.htm

 CAS latency is an important metric to consider when building a new computer.

Good one Carlsbad

I am not sure of the answer.

I am sure this is not the place to find the answer.

So I have a pre-build computer, Acer Predator Orion 3000 with RTX 3070, i7 10700, and used to have 16gb 3200mhz ram.
I decided to upgrade to 32gb 3600mhz ram, and before I put those in when I checked task manager it said 2997mhz or something like that. Now when I have put in the new ones it says 2666mhz instead.
I have done some googling and seems I have to change stuff in BIOS, which I have tried but I can't do anything in there basically. Seems like my BIOS is very limited, is there some sort of advanced BIOS I can enter? In that case how?
I did put the new ram in the same slots, just confused how the Hz could go down. If I want the old speed back, can I put the old ones in and also put in the new ones to get more GB but the same speed?

I got this,..