Minimum PSU?

[Gray]

I've currently got new computer parts setup at the moment for a new build i'm doing in a few days. One thing i neglected, or should i say, thought of but didn't think it would be an issue, is PSU ability.

My last upgrade was 4-5 years ago, and my Enermax PSU 620w has been perfectly fine, in the back of my mind i thought i should consider getting a new PSU but i held off on that choice after doing some basic research into it.

A lot of reputable websites say 620w is fully capable, whereas some say it absolutely isn't so now i'm considering going out and buying a Corsair CM 750w-M. At the same time, 620w may be fine - But it could be also a risk of using a PSU a good few years old in a brand new setup which could be the risk.

Asus Z170 Pro Gaming Motherboard [1151]
i5 6600k
Gigabyte GeForce GTX 970 G1 Gaming
16gb DDR4 Corsair
3 SSDs + 1 HDD

When i first asked about the PSU it was when i was looking at a GTX 960, but then the opportunity to get the 970 G1 came up i couldn't refuse

 

[ECA]

Your current psu is fine.

the newer processors use even less power, same with newer gpus.

Your max draw there is like 475W, if cpu and gpu are under full load.
SSDs require fuck all power.

 

[caLLous]

Yup, no problem. Run your usage scenario through something like this (I was looking for one that wasn't affiliated with a PSU manufacturer but none of them seem to have the Skylake CPUs on yet) to give you a ballpark figure of wattage. I put the specs you gave us in and it came up with 371W.

 

[Gray]

yeah in my checking up i seen that site and a couple more putting it on all, Asus wasn't accurate on their power consumption because they don't seem to have updated their website for 1151 sockets nor any recent nVidia graphics cards etc, but on the ones that did have the information they all said 400-500w.



When i did talk to one of my colleagues about it, who know a bit more about the electronic sides of computing, they said it's risky because the Gigabyte GeForce is a bit of a monster on power consumption, and during the initial boot stages there might not be enough "amp" to fire up the PSU and i'd just get black screened.

Bearing in mind my Enermax 620w is also a few years ago, and doesn't come rated (like bronze for instance) so while i feel both sides do have points each, is it worth risking £500+ for a new £50 PSU which may or may not be needed.

I have banged through the Corsair on Flubit mind.

My other possible test was to even plug my Gigabyte card into my current setup and see how it ran.

 

[caLLous]

I think I said 2x8GB DDR4 modeuls and a 5400RPM HDD and no optical, which would explain the difference.

The 970 isn't a very high consumer by today's standards. Figures for the Gigabyte GTX 970 G1 Gaming show it peaking at about 160W on a GPU stress test (presumably something like Furmark which pushes the consumption much higher than even intensive gaming).

 

[old.Osy]

With a 620W PSU, even at 80% efficiency, you will be more than fine with that setup.

Unless you are planning to add more graphic cards and/or classic spin disks, you're fine, with some room to spare, even.

 

[SFXman]

Another voice chiming in, 620W definitely good to go.

The Corsair 750W would honestly handle 970 SLI, unless you OC to a severe extent.