PSU - how much of a fudge factor?

[Oxians]

Hello good people of the community!

 

I have a conundrum that I need to solve.

I am buying a PSU soon, and will buy a new PC in ~6 months that it will need to power.

 

A quick rundown of the planned load on it:

• i7-4970K (overcloked in a safe-ish way)
• GTX 980
• 1 SSD
• 2 HDDs
• A few USB devices
• 5 120mm fans

 

Specifics may change in the meantime, but that is the power level I am looking to support.

I don't plan to go for SLI.

 

OuterVision calculator recommends 411W

Then I look at the capacitor aging footnote...

I plan to run this thing most of the time, for years on end (I plan to not change the PSU for at least it's warranty period - 7 years)

So, going for the maximum selection of 50%, i get 600W

 

However, I have a gut instinct to go - sure, that might work, but it'll be stressed - throw 850W at it, so it doesn't go above 75% power.

On the other hand, I'm layering fudge factors here...

Also, I know I should look to keep the utilization in the 20% - 70% range for best efficiency.

 

By the way, I am looking at the Seasonic X Series SS-850KM3

 

 

Finally, my question is:

Does this much "fudge" cross into lunacy?

If you had a choice of 650W, 750W or 850W, which would you choose here, if you planned to run it for 7+ years and through at least two complete PC overhauls?

 

 

Thank you in advance!

[paprikman]

• snip

Seasonic is a good choice, the best psu's for me on the market.

650w should be enough for u.

In fact, u'll hardly reach a point of 400w consumption... Maybe, never.

[WhatComesAround]

Any corsair or CM PSU will be good as long as you get a CM one that is V or VS and as long as it is more than 500W

[ShadowCaptain]

Personally I am using an 850 watt, meaning if I decide to expand later maybe to SLI or to something more power hungry my PSU should keep up with what I am doing

[ZetZet]

If you don't plan to sli 500+, if you do 700+.

[H4X3R]

Eh, just get an EVGA G2 750W lol, good for future SLI / CFX if you so desire.

[Samfisher]

Hello good people of the community!

 

I have a conundrum that I need to solve.

I am buying a PSU soon, and will buy a new PC in ~6 months that it will need to power.

 

A quick rundown of the planned load on it:

• i7-4970K (overcloked in a safe-ish way)
• GTX 980
• 1 SSD
• 2 HDDs
• A few USB devices
• 5 120mm fans

 

Specifics may change in the meantime, but that is the power level I am looking to support.

I don't plan to go for SLI.

 

OuterVision calculator recommends 411W

Then I look at the capacitor aging footnote...

I plan to run this thing most of the time, for years on end (I plan to not change the PSU for at least it's warranty period - 7 years)

So, going for the maximum selection of 50%, i get 600W

 

However, I have a gut instinct to go - sure, that might work, but it'll be stressed - throw 850W at it, so it doesn't go above 75% power.

On the other hand, I'm layering fudge factors here...

Also, I know I should look to keep the utilization in the 20% - 70% range for best efficiency.

 

By the way, I am looking at the Seasonic X Series SS-850KM3

 

 

Finally, my question is:

Does this much "fudge" cross into lunacy?

If you had a choice of 650W, 750W or 850W, which would you choose here, if you planned to run it for 7+ years and through at least two complete PC overhauls?

 

 

Thank you in advance!

 

400w is the total system power at full load on both CPU and GPU.  Best PSU efficiency is between 50-75% total wattage.  I'd go 750w minimum to be able to add in another 980-class GPU in the future if ever.  650w will power this thing more than adequately.  Using a 650w PSU for the past 5 years, i5-3570K @ 4.4GHz, GTX 970 overclocked with custom BIOS and voltage settings, and all 6 SATA ports occupied with 3 SSD's and 3 HDD's, a sound card, a DVD drive.

[Lord_Karango17]

Only reason to go over 650W would be to make sure that no matter what you change in your system, you wont need to get a new PSU...

[Oxians]

Thanks everyone.

With your input I may go down a step to 750W. Too paranoid to go any further

[Aniallation]

Thanks everyone.

With your input I may go down a step to 750W. Too paranoid to go any further

750W is still much more then you need if you don't plan to SLI tbh