Watt requirements for overclocking

[Emillionaire]

Hi, so i am currently looking after a PSU. 

I'm thinking about the Corsair CX-M Series CX450M (as it fits my budget, and it is placed in Tier 3 on the PSU Tier list.) 
Asking around i was told that there is enough watt for me to be able to overclock my system, and Cooler masters watt calculator also tells me that its enough, but

when looking on the pinned post with "How many watts do i need" it says that a FX-8 core, Unlocked i5 or Xeon says: Minimum recommended PSU with overclock OR future dual GPU: 550W. 

Is a i5 using more watt than my i7? What is it that i am not seeing? I wish to overclock it to around 3.4Ghz
Thank you for all the help. 

 

Full parts list:
CPU: i7 960

GPU: Asus STRIX GTX 960

RAM: 2*4GB DDR3 RAM

Mobo: intel-dx58so
SSD: 120GB, not yet decided.
HDD: 1TB, not yet decided.
Extra: DVD/CD Drive, and maybe Ethernet/WIFI card.

 

 

[79wjd]

What GPU are you using? 

 

An i5 uses less power than an i7, but it's worthwhile pointing out that you could overclock a 7700k+GTX1080 on a good 400w psu. 

[Emillionaire]

Just now, djdwosk97 said:

What GPU are you using? 

A GTX 960. I will put the full part list in the post. 

[79wjd]

Just now, L0gic said:

A GTX 960. I will put the full part list in the post. 

A CX450m is more than enough, your system won't pull more than like 250-300 watts.

[Emillionaire]

2 minutes ago, djdwosk97 said:

A CX450m is more than enough, your system won't pull more than like 250-300 watts.

Okay, thank you. But what is it that i am missing? 
I dont understand it. I feel kinda stupid right now. 

[79wjd]

Just now, L0gic said:

Okay, thank you. But what is it that i am missing? 
I dont understand it. I feel kinda stupid right now. 

What are you confused about? 

[Emillionaire]

2 minutes ago, djdwosk97 said:

What are you confused about? 

A i5 uses less power, and the "how many watts do i need" post says that it needs 550W when overclocked, but an i7 which uses more power only needs 450W when overclocked? I dont get it.

[79wjd]

2 minutes ago, L0gic said:

A i5 uses less power, and the "how many watts do i need" post says that it needs 550W when overclocked, but an i7 which uses more power only needs 450W when overclocked? I dont get it.

He's being generous and taking into account lower quality units. You can overclock an i5/i7+GTX 960 on a good 300 watt psu, but then you have no headroom if you wanted to throw in something more power hungry. 

[Emillionaire]

1 minute ago, djdwosk97 said:

He's being generous and taking into account lower quality units. You can overclock an i5/i7+GTX 960 on a good 300 watt psu, but then you have no headroom if you wanted to throw in something more power hungry. 

Okay, thank you very much. Then i'll order the corsair CX-M Series CX450M.

[STRMfrmXMN]

5 hours ago, L0gic said:

A i5 uses less power, and the "how many watts do i need" post says that it needs 550W when overclocked, but an i7 which uses more power only needs 450W when overclocked? I dont get it.

He's recommending that for a safety cushion. It's a good idea to have a unit capable of outputting that much to begin with. For an old i7 and 960 you'll never draw more than 200W of power so you're fine with the CX450M.