power supply calculators

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hoek88

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Are these sites reliable in what results they give?

http://www.coolermaster.com/power-supply-calculator/

https://images10.newegg.com/BizIntell/tool/psucalc/index.html?name=Power-Supply-Wattage-Calculator

https://www.msi.com/power-supply-calculator

All but cooler master saying that my PSU should be enough


I have a SeaSonic S12II 620 Bronze 620W

I wanna put a second video card in my machine because it's not being used.

2x XFX AMD Radeon 6970's

My proc is i5 sandy bridge 2500k @ 3.3
4x4gb of DDR3
maybe 2 samsung SSD's @ 512GB


ALSO

I'm probably just gonna end up buying a 1200W and just get it over with but why are all the Seasonic sold out everywhere!? I looked on newegg, tigerdirect, pricewatch...

Can anyone recommend another brand? I dont think you can beat Seasonic for the money...
 
Power supply calculators are not very accurate.

6970s are about 220-240 watts each stock. A 2500k is around 70 watts stock. Rest of system is 50 watts. You are fine keeping everything stock.

1200 watts is a complete waste of money for your system.
 
Tsumi said:
Power supply calculators are not very accurate.

6970s are about 220-240 watts each stock. A 2500k is around 70 watts stock. Rest of system is 50 watts. You are fine keeping everything stock.

1200 watts is a complete waste of money for your system.
Click to expand...

So right there it sounds like the full wattage of my PSU. And then if I put any sort of load on it with a game for e.g. I'm probably gonna start dancing around the max wattage of my PSU and possibly fry some components.
I mention buying a 1200 watt because I'll probably throw in a 3rd card for the "luls"
 
hoek88 said:
So right there it sounds like the full wattage of my PSU. And then if I put any sort of load on it with a game for e.g. I'm probably gonna start dancing around the max wattage of my PSU and possibly fry some components.
I mention buying a 1200 watt because I'll probably throw in a 3rd card for the "luls"
Click to expand...

When he mentioned 220-240 watts, that was under load.
 
auntjemima said:
When he mentioned 220-240 watts, that was under load.
Click to expand...
I know the TDP is 250 and at idle its around 20. But I'm obviously going to be playing games. I just wanna be sure before I stick this thing in my PC and fire up a game and then end up having to replace my mobo or something.
 
Seasonic PSUs are rated for continuous usage. Yours should theoretically be able to do 620 watts 24/7.

Gaming typically uses less than TDP. And no, you won't fry anything, if your PSU is unhappy with the load it will shut off.
 
Well, shutting off is just the best case scenario of what can happen with under voltage problems. How's Corsair for the PSU market? Because Seasonic out of stock everywhere I look...
 
I always used this when I spec out a PC.

No gpu quality 300 watt

One gpu quality 400-520 watt

2 quality 700-800 watt

More than 2 cards you're wasting money.
 
On a ~good~ power supply, undervoltage won't happen, they will shut down on overload before they hit that point. On a bad one, anyone's guess.

That being said, Seasonic definitely tend to fall into the "Good" category. Corsair, mostly in the good category but your going to pay a premium for the name. Some of their lines are just average, but your going to pay more for them than you would a rockstar Seasonic.

Pretty much any brand your looking at, you need to look up several reviews of the exact model you are looking at. Most PSU vendors are just rebranded something else, and can use various brands underneath their sticker for various models. It's not uncommon for a PSU supplier to have a few good units, and a few units that are less than stellar on their label. Only by looking at them model by model can you weed out the wheat from the chaff.

For calculators, the method Tsumi mentions is pretty accurate - at stock clocks, add up the TDP of all your major components. Add another 50-100W on top of that for miscellaneous loads and contingency, and that's a good baseline wattage to aim for. If you plan on attempting to aggressively overclock, double the TDP wattage for the component you intend on overclocking.
 
looks like my current PSU doesnt even have the pins I need for the two cards.
My current PSU says it has

1 x Main connector (20+4Pin)
1 x 4/8-Pin ATX 12V / EPS 12V

So the 24-pin EATXPWR, and the 8-pin EATX12v



So total:
24-pin EATXPWR, 8-pin EATX12v
2x6 PCI-E and I would need 2x8 PCI-E pin

I guess the question is now, for that extra 8-pin EATX12v

I cant find any PSU ranging in the 1000w that have that 8-pin AND 2x6 PCI-E and 2x8 PCI-E
 
ATX12v/EPS12v are entirely different connectors from PCI-E 12v.

Most modern PSUs do not have 8-pin PCI-E connectors, they have what are called 6+2, which means they can be used as 6 or 8 pin connectors. All quality PSUs in the 750 watt range should have at least 2 6 pin and 2 6+2 pin PCI-E connectors, if not 4 6+2 connectors, and many in the 650 watt range would have that as well.
 
Tsumi said:
ATX12v/EPS12v are entirely different connectors from PCI-E 12v.

Most modern PSUs do not have 8-pin PCI-E connectors, they have what are called 6+2, which means they can be used as 6 or 8 pin connectors. All quality PSUs in the 750 watt range should have at least 2 6 pin and 2 6+2 pin PCI-E connectors, if not 4 6+2 connectors, and many in the 650 watt range would have that as well.
Click to expand...
Would these do? Or something similar to these specs

https://www.newegg.com/Product/Product.aspx?Item=N82E16817139140

https://www.newegg.com/Product/Product.aspx?Item=N82E16817152072
 
Tsumi said:
ATX12v/EPS12v are entirely different connectors from PCI-E 12v.

Most modern PSUs do not have 8-pin PCI-E connectors, they have what are called 6+2, which means they can be used as 6 or 8 pin connectors. All quality PSUs in the 750 watt range should have at least 2 6 pin and 2 6+2 pin PCI-E connectors, if not 4 6+2 connectors, and many in the 650 watt range would have that as well.
Click to expand...
Thermaltake any good?

https://www.newegg.com/Product/Product.aspx?Item=N82E16817153155
 
I use TDP values of every component added together (CPU say 100w, Mobo 50w, GPU 2x 250W and rest of the system another 50W, totaling 700W) then adding 20% on top of that (840W).

AFAIK Seasonic completely stopped making modular PSUs under 850W, so X-850 would have been my pick from Seasonic.
 
chenw said:
I use TDP values of every component added together (CPU say 100w, Mobo 50w, GPU 2x 250W and rest of the system another 50W, totaling 700W) then adding 20% on top of that (840W).

AFAIK Seasonic completely stopped making modular PSUs under 850W, so X-850 would have been my pick from Seasonic.
Click to expand...

A 2500k uses quite a bit less than 100 watts. Unless you have an older X58 or AMD AM2/3 motherboard, or one of those with the built-in PCI-E multiplex chips or LSI chips, motherboards don't consume anywhere close to 50 watts.

The Prime 650 watt, Platinum 400 watt, 760XP2 and so on would all like to have a word with you regarding full modularity, let alone partial modularity of other model lines.
 
Tsumi said:
A 2500k uses quite a bit less than 100 watts. Unless you have an older X58 or AMD AM2/3 motherboard, motherboards don't consume anywhere close to 50 watts.

The Prime 650 watt, Platinum 400 watt, 760XP2 and so on would all like to have a word with you regarding full modularity, let alone partial modularity of other model lines.
Click to expand...

I know that, but I always buy more than what I need as it gives me more wiggle room with my system later down the line. I have never been able to get an accurate TDP of motherboards so I just calculate them as 50W.

I'd only start to accurately going after the proper wattage if I was on a strict budget, but Seasonic is not really a budget oriented brand PSU anyway, there are plenty of top tier rated PSUs of similar wattage that is significantly cheaper.

And I stand corrected on the modularised units. I only noticed that X-650 (my previous rig's PSU) was no longer available and G-650 wasn't fully modularised, so I had assumed they did away with modularisation with the lower wattage gold PSUs and reserved them for Platinums. The prime series completely slipped past my radar.
 
chenw said:
I know that, but I always buy more than what I need as it gives me more wiggle room with my system later down the line. I have never been able to get an accurate TDP of motherboards so I just calculate them as 50W.
Click to expand...

But that's pointless: TDP Is going down as time passes, not up. Those 6970, they are 250W but the GTX 750 is comparable in performance as per https://www.futuremark.com/hardware/gpu/AMD+Radeon+HD+6970/review and it's 75W! Today you need to buy an 1080 Ti to get a 250W card and there's barely any point in running two cards these days (no VR titles support them etc) and literally every (consumer) card out there consumes less.
 
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chx said:
But that's pointless: TDP Is going down as time passes, not up. Those 6970, they are 250W but the GTX 750 is comparable in performance as per https://www.futuremark.com/hardware/gpu/AMD+Radeon+HD+6970/review and it's 75W! Today you need to buy an 1080 Ti to get a 250W card and there's barely any point in running two cards these days (no VR titles support them etc) and literally every (consumer) card out there consumes less.
Click to expand...

Say that to AMD...

PSU is one of the things that my golden rule of "just enough isn't enough" applies strictly. I never buy just enough wattage for my system, I always get a tier higher because TDP decreases are not consistent between the two companies, and I'd absolutely HATE the feeling that I am not able to jump from one side to another because one side isn't up to par with respect to their TDP than the other. I prefer to keep my options open.

Until AMD can release GPUs that are equally as efficient in power usage as nV, I will spec my own machine with the worst case scenario.
 
I built a PC last year:

6700K, 3x SSDs, a handful of fans, AIO Watercooler, 2x 970's, and a few other goodies internally.

Running stress tests, with a kill-a-watt, it was ~575 Watts at the wall. My 750 PSU is more than enough for that.

for 1300? You'd need a HELL of a computer....
 
You were told your PSU should be fine, you are also not having problems with the current PSU, yet you seem dead set on getting a new one, and not just any old new one, but a 1k+ watt one even though you have been told over and over you don't need that much. Are you just hunting for reasoning to get a new over 1k watt PSU or something? If that is the case, just say so and people can suggest a 1k watt+ PSU for you, if not, then listen to the others, and buy a QUALITY 750-850 watt PSU and call it a day, and no, your under $90 1,000Watt RAIDMAX PSU you linked would not be on the list for me.
 
my current 620 watt psu did not have the extra 6 & 6+2 power connectors for my second GPU. Therefore I needed a PSU that provided that. I have taken the comments into consideration and I appreciate everyone's input. It has been very resourceful. I may pick up a 3rd video card just to try it. For 60$ dollars I don't think it's an overly expensive splurge of money.
 
You may as well keep your current PSU and use the money you would spend on a quality 1000 watt PSU and get a 1070 or something similar instead. You will get far better performance than crossfire or trifire 6970s. Buying a 1000 watt PSU to run 3 4-generation old GPUs makes absolutely no sense.
 
I already had the 2nd card. I'm not going out of my way to run these cards. I said I can pick up a third for 60 bucks. Whats the big deal? lol I understand the cons outweigh the pros for any crossfire or sli machine i just thought it would be fun to goof around and try it.
 
hoek88 said:
I already had the 2nd card. I'm not going out of my way to run these cards. I said I can pick up a third for 60 bucks. Whats the big deal? lol I understand the cons outweigh the pros for any crossfire or sli machine i just thought it would be fun to goof around and try it.
Click to expand...

Because you want to spend another $150+ on a PSU and then another $60 on another GPU for triple xfire, where performance scaling is not great and depends on game support etc etc when you could save the money from the PSU and 3rd GPU, sell the other two GPUs you have and get a single new card that will blow that triple xfire out of the water, not have to worry about game support, consume less power and dump far less heat into the case. And once you realize that, you will understand why you are getting the suggestions you see here.
 
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And if you can't find a seasonic of 750w in stock, look at some of the other big brands, EVGA and corsair are 2 that spring to mind
 
The sites are obviously not fully accurate they only provide an estimate.
As for what the others have said, go with that. You WON'T fry your PC with load going above PSU limit, it will shut down.
Secondly, 650Watts is more than enough to light up two GPUs, one CPU and couple of hard drives. If it is SSD, it will take even less power.

Still if you want to change, go for a 750W at max.

Here are a few options: http://www.memory4less.com/cooler-master-power-supply
http://**************/2uy32T2
 
Whether or not it is enough power is not the problem... the problem is that there are not enough PCI-E connectors on my current PSU to plug into a second card.

I do now have a new PSU with enough PCI-E cables but still having trouble with it. My motherboard is an Asus P8Z68 with an (8pin EATX 12V) and the PSU has these connectors

ATX Cable (24-pin)
EPS12V CPU Cable (8-pin) labeled CPU
ATX/EPS 12V CPU Cable (4+4pin) not labled

I've tried the (8-pin) and the (4+4pin) both and two of my motherboards don't boot. It powers up for a second but powers right back down. As soon as I stick the Seasonic back in my mobos boot right up.

To be honest I don't understand what the difference is between the two CPU cables. I'm assuming my mobo takes the 4+4... but again I've tried both nothing seems to work I'm probably going to RMA this PSU back... Maybe I'm doing something wrong? Could I have fried the PSU by using the wrong CPU cable? my motherboards are fine...
 
If you OC most of your stuff I find these calculators underestimate power requirements by ~100W. If you run everything at stock they are probably pretty reliable. The MSI one is useless but the cooler master one was okay. The reason I know this is I had a 1070 (max around 300W draw) and had no problems. Recently got a 1080ti (~400W draw) and now I'm getting shutdowns intermittently when load is too high. Using an excellent PSU as well, seasonic 750W.
 
robertdane101 said:
The sites are obviously not fully accurate they only provide an estimate.
As for what the others have said, go with that. You WON'T fry your PC with load going above PSU limit, it will shut down.
Secondly, 650Watts is more than enough to light up two GPUs, one CPU and couple of hard drives. If it is SSD, it will take even less power.

Still if you want to change, go for a 750W at max.

Here are a few options: http://www.memory4less.com/cooler-master-power-supply
http://**************/2uy32T2
Click to expand...
I was reading that while SSDs do take less average power, they take a higher peak power. Peak power is what's relevant when dealing with PSUs
 
Hard drive spinup takes significantly more power than an SSD would ever use. The other thing about peak power is that you would rarely see simultaneous peak power usage from all components in real world usage.
 
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