Question How much Power do I really need?

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Nov 17, 2021
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So I want to get a new psu, since my old one was always constantly turning off for no real reason. I don't really want to spend too much on a power supply, however, so I need some tips. Say if there is enough connectors for everything I need, does that mean it is enough power? If not, here are my specs:
MB: hp elitedesk 800g1 sff
PSU: Undetermined
Cpu: Xeon e3 1220 V3
Cooler: Stock
RAM: 8gb ddr3
gtx 770 2gb gddr5
2tb 7.2k rpm HDD
256gb (I think) PM851 samsung SSD
5 ~1200 rpm fans
I was thinking if a 550w psu would be enough.
Thanks!
 
Something wrong with the brand?

Yes. It's one of many deep discount brands that use cheap, low-quality parts. If you want a cheap, low-quality PSU that suffers under load, you can keep using your current one for free, which is a better price.

The first page has multiple links to the least expensive PSUs worth spending money on. The omission of any Aresgame PSUs from the recommendations was not accidental.
 
Yes. It's one of many deep discount brands that use cheap, low-quality parts. If you want a cheap, low-quality PSU that suffers under load, you can keep using your current one for free, which is a better price.

The first page has multiple links to the least expensive PSUs worth spending money on. The omission of any Aresgame PSUs from the recommendations was not accidental.
Ok
 
You can cheap out on every other component inside the PC except PSU. Since PSU powers everything, it is the most important component inside the PC. Also, while the PSU warranty covers the PSU itself and you can RMA the blown PSU, the PSU warranty doesn't cover any other component the PSU fried.

Most people learn the hard way not to cheap out on a PSU when low quality PSU blows and takes part of the system or the whole system with it. Even entire houses have been burned down because of the fire low quality PSU caused when it blowed up.

Like it or not, if you want your PC to work for years to come without any risk of fire and/or damage to your components, you need to hand out some money for good quality PSU. I'm not talking that you need to go with the best PSU money can buy, e.g Seasonic PRIME 650 (80+ Titanium), which costs $150+ (and which also powers my Skylake build). Seasonic Focus GM-650 shared above, costs $48 (after rebate) and is more than enough for your PC, both wattage and build quality wise.

However, if you go with "budget" PSU, please, do record a video when your cheap PSU blows up since i like to see some good fireworks. Just like seen in here,
youtube:
View: https://www.youtube.com/watch?v=f6snWfd1v7M


If you still think "budget" PSU is best for your PC, i'll be waiting a video from you with good fireworks.
 
You can cheap out on every other component inside the PC except PSU. Since PSU powers everything, it is the most important component inside the PC. Also, while the PSU warranty covers the PSU itself and you can RMA the blown PSU, the PSU warranty doesn't cover any other component the PSU fried.

Most people learn the hard way not to cheap out on a PSU when low quality PSU blows and takes part of the system or the whole system with it. Even entire houses have been burned down because of the fire low quality PSU caused when it blowed up.

Like it or not, if you want your PC to work for years to come without any risk of fire and/or damage to your components, you need to hand out some money for good quality PSU. I'm not talking that you need to go with the best PSU money can buy, e.g Seasonic PRIME 650 (80+ Titanium), which costs $150+ (and which also powers my Skylake build). Seasonic Focus GM-650 shared above, costs $48 (after rebate) and is more than enough for your PC, both wattage and build quality wise.

However, if you go with "budget" PSU, please, do record a video when your cheap PSU blows up since i like to see some good fireworks. Just like seen in here,
youtube:
View: https://www.youtube.com/watch?v=f6snWfd1v7M


If you still think "budget" PSU is best for your PC, i'll be waiting a video from you with good fireworks.
Quote taken. Would you have any psu that you know of that is around $50?
 
Don't cheap out on the PSU, once you get yourself a great unit, it will be with you years too come powering on and keeping your rig stable.

The thought that one must have when it comes to upgrading or replacing a PSU should be "how much power do I want to utilize?" instead of "how much power do I need?"
 
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You can cheap out on every other component inside the PC except PSU. Since PSU powers everything, it is the most important component inside the PC. Also, while the PSU warranty covers the PSU itself and you can RMA the blown PSU, the PSU warranty doesn't cover any other component the PSU fried.

Most people learn the hard way not to cheap out on a PSU when low quality PSU blows and takes part of the system or the whole system with it. Even entire houses have been burned down because of the fire low quality PSU caused when it blowed up.

Like it or not, if you want your PC to work for years to come without any risk of fire and/or damage to your components, you need to hand out some money for good quality PSU. I'm not talking that you need to go with the best PSU money can buy, e.g Seasonic PRIME 650 (80+ Titanium), which costs $150+ (and which also powers my Skylake build). Seasonic Focus GM-650 shared above, costs $48 (after rebate) and is more than enough for your PC, both wattage and build quality wise.

However, if you go with "budget" PSU, please, do record a video when your cheap PSU blows up since i like to see some good fireworks. Just like seen in here,
youtube:
View: https://www.youtube.com/watch?v=f6snWfd1v7M


If you still think "budget" PSU is best for your PC, i'll be waiting a video from you with good fireworks.
Ok so, I did a little digging and found a new, EVGA 700BR on bestbuy for 44.99 with the holiday discounts. All new, everything. Would you recommend it?
 
I cant see anything wrong with what you mentioned, besides only having 100.000 hours MTBF and 700Watt, 58.3 Amps on the 12 volt rail...

Do some calculations and see if you are planning to use it that long , before having to replace it due to failure or you requiring more power due to a next pc part upgrade.
Ok so, I did a little digging and found a new, EVGA 700BR on bestbuy for 44.99 with the holiday discounts. All new, everything. Would you recommend it?

I had a secondhand EVGA PSU unit once, it was 1200watt and the pc it was installed in did not even require 300watt total, there was never any stability to be had.
 
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I cant see anything wrong with what you mentioned, besides only having 100.000 hours MTBF and 700Watt, 58.3 Amps on the 12 volt rail...

Do some calculations and see if you are planning to use it that long , before having to replace it due to failure or you requiring more power due to a next pc part upgrade.
what does 100 mtbf mean?
 
what does 100 mtbf mean?
It means the: mean time before failure, estimate life span of unit.

But now that I have calculated that myself it seems they estimate 11years of continues use on the same hardware setup before failure is to be expected.

But that might not be if you change hardware setup many times over the years or start of using the unit and overtaxing it right from the start.
 
It is 100.000 hours so it's not 100 like you are reading, 100.000 hours MTBF seems like 11years.

EVGA - Products - EVGA 700 BR, 80+ BRONZE 700W, 3 Year Warranty, Power Supply 100-BR-0700-K1 - 100-BR-0700-K1

Seems pretty decent if you think about it, it's only warrantied for 3 years but expected to run 11years under the right circumstances.
PFFFFFFFFFT! This is my rig for now. I'm waiting until I can be financially stable enough to get a full rig (aka ~1 year max 2) so 11 years is totally fine.
 
What's wrong with the Corsair CX650?

It's a mediocre PSU and only good for office builds without dedicated GPU. That's what's wrong with it.
And that's not all. CX650 is made by CWT and Great Wall and when you buy one, there's no telling which of the two you'll be getting.


Older models of Corsair CX and CXm series (with green labels) were so bad units that they ended up as low quality units (on-par with current Corsair VS series). Corsair has since improved their CX and CXm line (with gray labels) and now, they are better but not enough to be considered as good quality PSU. Bulk of Seasonic units are either good quality or great quality (depending on the series).

While CX series are cheap, you won't get solid build quality and all Japanese caps as you can get with many Seasonic units. Here's one in-depth review of CX650, the Great Wall version,
link: https://www.tomshardware.com/reviews/corsair-cx650-power-supply-review

Corsair CX650 does provide some good results but it also provides some bad results. Like hold-up time that is way lower than the ATX standard specifies it to be. CX650 has hold-up time of 8.30 milliseconds while the ATX standard for hold up time is a minimum of 17 milliseconds. For comparison, Seasonic PRIME 650 80+ Titanium (one of the best 650W PSU money can buy) has hold-up time of 30 milliseconds.

And it's just not the hold-up time, there are other, more apparent things that doesn't make it good quality unit. One of them is transient response at +12V and +3.3V. With load changes, PSU is struggling to keep the voltage stable and within ATX standard specs, while at +3.3V rail, it fails to keep voltage within ATX standard. And off-spec voltages mean damage to other components, either frying them on the spot or gradually damaging and shortening components lifespan.

It being fully-wired doesn't help either, since with that, you will have leftover cables that you have to somehow place somewhere. With semi- or fully-modular cables, you only use what you need.

Since CX650 has nice list of good things and also bad things, it's a mediocre quality unit. If there were more bad than good (including price) it would be a bad unit and vice-versa.


I, personally, wouldn't use it. While it can be used just fine for an office PC that never sees any high loads. But for home use in a gaming PC, where PC components longevity is important factor, i'd use and also suggest using better quality PSU.

Different persons have different standards (some have higher standards while others have lower standards) and it's up to every person to decide how good of a build quality components are safe to use in their PC. But keep in mind that PSU is the most important component inside the PC since it powers everything.

Since i care a lot about all my PCs, i won't put a mediocre quality unit into my PC that fails to meet ATX PSU standards set in place for all OEMs to follow, so that the PSUs are safe to use and doesn't damage other components. In fact, i've gone above and beyond regarding PSUs in my PCs.
Some may call me nuts that i payed €206.80 for a PSU that sits in my Skylake build (Seasonic SSR-650TD) and my latest PSU purchase for Haswell build costed €205.50 (Seasonic SSR-650TR), while i would've been safe with a PSU that costs €80.50 (Seasonic GX-550). While that can be true and i could've saved a lot of money, i feel safe and comfortable that my two main PCs are powered by the best offered by Seasonic.

I won't suggest expensive PSUs in builds when the budget is way restricted. But i still suggest getting a PSU that at least meets all the ATX PSU standards, like Seasonic Focus GM-650 linked above.
Focus GM-650 review: https://www.thefpsreview.com/2021/05/04/seasonic-focus-gm-650-650w-power-supply-review/

Btw, Seasonic Focus GM-650 comes with 7 years of warranty, 2 years more than Corsair CX650.
 
You really don't know what you're talking about!

And you do?

CX650 may be enough for your standards, but for me, it is mediocre and i'm not the only one who thinks so.

From https://forums.tomshardware.com/thr...pply-discussion-thread-toms-hardware.3212332/

The non-green label "2017" CX models are slightly better than the CXm units. For a budget entry level unit, they are fairly decent. They are not great or fantastic, but they ARE ok, if this is ALL you can possibly afford. Don't buy one of these expecting it to last as long as an RMx or EVGA G2 unit though. It's not going to. It's a good entry level offering and that is all.
 
From https://forums.tomshardware.com/thr...pply-discussion-thread-toms-hardware.3212332/

https://forums.tomshardware.com/goto/post?id=19794759
The non-green label "2017" CX models are slightly better than the CXm units. For a budget entry level unit, they are fairly decent. They are not great or fantastic, but they ARE ok, if this is ALL you can possibly afford. Don't buy one of these expecting it to last as long as an RMx or EVGA G2 unit though. It's not going to. It's a good entry level offering and that is all.
That is al that the Op is looking for. Think he will be fine.


Here you go:
Seasonic focus gm 650 for $48 after $15 rebate card.
7 year warranty:
https://www.newegg.com/seasonic-focus-650-gold-ssr-650fm-650w/p/N82E16817151202?quicklink=true
If rebate is an option is this a good choice too.