How should I upgrade MSI X99A Gaming RIG

[average25]

Any suggestions on how to upgrade this PC it was a gift to me and I'm relatively new to modding systems. The specs are below any suggestions would be greatly appreciated
CAS: LEPA Lenyx E-ATX Gaming Case w/ Black Rubber Coating Skin, USB 3.0, 2.5" Hot-Swap, 2x 200mm & 140mm Fans [+51]
CD: LG 14X Internal Blu-ray Burner, BD-RE, 3D Playback DVD+RW Combo Drive (Black Color)
COOLANT: Standard Coolant
CPU: Intel(R) Core™ i7-5820K Six-Core 3.30GHz 15MB Intel Smart Cache LGA2011-V3
CS_FAN: Default case fans
FAN: Asetek 550LC 120mm Liquid Cooling CPU Cooler - Extreme Cooling Performance (Single Standard 120MM Fan)
HDD: 2TB (2TBx1) SATA-III 6.0Gb/s 64MB Cache 7200RPM HDD (Single Drive)
IUSB: Built-in USB 2.0 Ports
MEMORY: 16GB (4GBx4) DDR4/2400MHz Quad Channel Memory (Corsair or Major Brand)
MOTHERBOARD: MSI X99A GAMING 9 ACK ATX w/ USB 3.1, 802.11 WIFI+BT 4.0, Killer GbLAN, 5x Gen3 PCIe x16, 1x M.2, 8x SATA 6Gb/s, 2x SATA Express (All Venom OC Certified) [+221]
Monitor Asus PB328Q 2560x1440
NETWORK: Onboard Gigabit LAN Network
OS: Windows10
No Overclocking
POWERSUPPLY: 600 Watts - Standard 80 Plus Certified Power Supply - SLI/CrossFireX Ready
SOUND: HIGH DEFINITION ON-BOARD 7.1 AUDIO
VIDEO: NVIDIA GeForce GTX 980 4GB GDDR5 PCIe 3.0 x16 (Maxwell) [+249] (Single Card)

 

[Niklas_13]

add a better PSU and enjoy it