Msi gtx 980 4g vs gtx 980ti ???

Hi to all im new, ive a MSI GTX 980 4G and i play on rog swift with 1440p.But a single card fill me to have compromised on games and filter, what you suggest sell it and take the 980ti (expected on this month) or go for sli?

Many tnx to all :puke2:

Msi gtx 980 4g vs gtx 980ti ???