How many watts should my power supply be?

[CamCam107]

Hey this is my first computer build and wanted to know how many watts i need in my power supply. here are the components:
Intel Core i7-3770K Quad-Core Processor 3.5 GHz 8 MB Cache LGA 1155 - BX80637I73770K
ASUS P8Z77-V LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
Corsair Vengeance 16GB (2x8GB) DDR3 1600 MHz (PC3 12800) Desktop Memory (CMZ16GX3M2A1600C10)
ASUS 2GB GDDR5 DIGI+ VRM technology Graphics Cards HD7770-2GD5 Western Digital WD1002FAEX Caviar Black 1 TB SATA III 7200 RPM 64 MB Cache Internal Desktop 3.5" Hard
Samsung 840 Series 2.5 inch 120GB SATA III internal Solid State Drive (SSD) MZ-7TD120BW
I was also wondering if you guys have any suggestions, and could you also tell me how i figure out how many watts I need, it would be much appreciated.

 

[Novuake]

Technically very little, decent 400W

Is this a gaming build?

Why are you getting an I7 but a low range graphics card?

Oh and the SSD. I would much rather suggest you get either the 830 or 840 Pro. They are both better than the 840 and the Pro version is one of the best SSDs available.

 

[ryanrich83]

You could probably get away with a 500W supply, as it would give you room to overclock.

[strike]The 7770 draws power from the motherboard, too. That lowers the power requirement.[/strike]

What is the main use for this machine? It is quite a beefy CPU for such a low tier graphics card.

 

[bigcyco1]

Radeon HD 7770 - On your average system the card requires you to have a 450 Watt power supply unit. If you are going to overclock the GPU or processor, then i do recommend you purchase something with some more stamina.

There are many good PSUs out there, please only buy a reliable power supply such as one of these http://www.newegg.com/Product/Product.aspx?Item=N82E16817207013
http://www.newegg.com/Product/Product.aspx?Item=N82E16817182066
http://www.newegg.com/Product/Product.aspx?Item=N82E16817151094
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703035

 

[Novuake]

You could probably get away with a 500W supply, as it would give you room to overclock.

The 7770 draws power from the motherboard, too. That lowers the power requirement.

What is the main use for this machine? It is quite a beefy CPU for such a low tier graphics card.

The HD7770 DOES NOT draw from the PCI-e slot...

 

[ryanrich83]

My bad. Was thinking of the 7750.

 

[CamCam107]

Hey, thank you all for your suggestions. now i have came up with the rest. I want it to be a gaming computer for around 1500 dollars. Please help me be leaving a comment of what I should change:
Intel Core i7-3770K Quad-Core Processor 3.5 GHz 8 MB Cache LGA 1155 - BX80637I73770K
ASUS P8Z77-V LGA 1155 Intel Z77 HDMI SATA 6Gb/s USB 3.0 ATX Intel Motherboard
Corsair Vengeance 16GB (2x8GB) DDR3 1600 MHz (PC3 12800) Desktop Memory (CMZ16GX3M2A1600C10)
ASUS GeForce GTX 680 DirectCU II OC Edition 2048MB GDDR5, DVI, DVI-D, HDMI, DisplayPort, Overclocked GPU and GPU Tweak Utilities PCI-Express 3.0 Graphics Card Graphics Cards GTX680-DC2O-2GD5
Cooler Master HAF X - Full Tower Computer Case with High Airflow Windowed Side Panel
and USB 3.0
Western Digital WD1002FAEX Caviar Black 1 TB SATA III 7200 RPM 64 MB Cache Internal Desktop 3.5" Hard Drive
Samsung Electronics 840 Pro Series 2.5-Inch 128 SATA_6_0_gb Solid State Drive MZ-7PD128BW
Cooler Master Hyper 212 Plus - CPU Cooler with 4 Direct Contact Heat Pipes (RR-B10-212P-G1)
Windows 8 Professional System Builder OEM DVD 64-Bit
Corsair CX Series 500 Watt ATX/EPS Modular 80 PLUS Bronze ATX12V/EPS12V 456 Power Supply CX500M