970 SLI in 2020

[Emillionaire]

Hi there. 
I've been having issues for some time with playing the new MW: Warzone, and with my PC underperforming in general. I have out of the PC game for a while, and therefore not up to date on how my hardware is doing. 
I feel like my GPU is getting quite low FPS on most games. Is the 970 outdated, and should i upgrade? I saw the exact same GPU used. Would SLI be possible/be a good idea? I've got a 650W Gold PSU, so my initial idea is yes. What is your opinion?

My build: 

CPU: Intel Core i7-6700 Skylake Processor
COOLER: Corsair Hydro Series H55 Cooler

MOBO: MSI H170A GAMING PRO, Socket-1151

RAM: HyperX Fury DDR4 2133MHz 8GB
GPU: MSI GeForce GTX 970 Gaming 4GB
SSD: Samsung 850 EVO 120GB SSD

HDD: Seagate Barracuda 1TB 3.5"
 

I've been having alot of issues when gaming. Not all feel FPS-related. Should there be a need to upgrade from an i7 6700 skylake?
Thx. 

[Way2Broke]

What issues? Crashing? Freezing?

[Emillionaire]

42 minutes ago, Way2Broke said:

What issues? Crashing? Freezing?f

Freezing/lagging for small periods. 

[Emillionaire]

40 minutes ago, NZgamer said:

SLI is not really support now, don't waste your money. Some games run worse in SLI. My suggestion is that you get another 8gb stick of ram. Your i7 Skylake is fine and so is the 970.

Sad, that haven't changed.. thx

But is the 970 really still doing well at 970? 

[Emillionaire]

1 hour ago, NZgamer said:

SLI is not really support now, don't waste your money. Some games run worse in SLI. My suggestion is that you get another 8gb stick of ram. Your i7 Skylake is fine and so is the 970.

Also, would my mobo support 16gb 3200hz ram?