Do I need to change my PSU?

[Avanta]

Hi,
I plan on replacing my GTX970 with a GTX1080, should I also buy a new PSU?

CPU: i7-6700K 4.5GHz
Cooler: Noctua NH-D15
Motherboard: ASUS Z170-A
RAM: Corsair 16GB @ 3000MHz
SSD: Samsung 850 EVO 500GB
HDD: WD Blue 1TB
GPU: ASUS GTX 970 STRIX
Case: NZXT H440
PSU: SeaSonic G 550W 80+ Gold
Case Fans: 5x Noctua NF-F12

How much overhead should I have? Please enlighten me.
Thank you

 

[nitinvaid20]

well Yes On your average system the card requires you to have a 600~650 Watts but A DECENT 650W-700W would be Enofgh