290X PSU Power Output Tests

SonDa5

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This is the first time I have done a power out put test, if I have made errors in my calculations please correct me. :)

When I got my 290X I didn't check the PSU requirements and assumed that my Seasonic Platinum 660XP PSU could handle it but when I found out AMD required 750W PSU I worried that my PSU may not be enough.

750 Watt Power Supply is required.
1X150 Watt 8-pin PCI Express power connector is required.
1X75 Watt 6-pin PCI Express power connector is required.

From Sapphire's WEB site:
http://www.sapphiretech.com/presentation/product/?cid=1&gid=3&sgid=1227&pid=2070&psn=&lid=1&leg=0#


After a few days of fun with the card and learning how to over clock it I decided to do a small PSU power output test for my own knowledge and to share.

My tests.


System Specs:

MB Asus Maximus VI Impact Z87
CPU 4770k over clocked to 4.8GHZ with 1.46v
AMD R9 290X over clocked to 1200/1600
2xSSD
1xSwiftech MCP655 Water Pump
1xBitFenix Hydra Pro 5 30W channel Fan controller
4x Scythe Gentle Typhoon 120 D1225C12B5AP-15 Fans
1x Scythe Ulta Kaze 120 x 38mm Fan

All Fans MAX RPMS for Max load.

CPU-Z Validation Link for System: http://valid.canardpc.com/1w43z4


Method of Power Testing

Multiply input voltage by max measured amps during different types of load. V x I = W or Voltage multiplied by Current equals Watts.

Order of testing and results from each test.


1. Voltage Input to PSU at 127.8 AC Volts as measured by Fluke 902 Fluke 902 True-rms HVAC clamp meter from electrical receptacle feeding PSU. (electrical measurements done with this electical testing meter)


PSUvoltagefeedtest.jpg




2. Measure max Amps of system with light usage surfing internet and streaming videos from youtube.


YoutubeSurfingAmps.jpg


127.8 Volts multiplied by 1.4 Amps equals 178.92 Watts.




3. Measure max Amps of system during Heaven benchmark.


heavenPSUtest.jpg


heavenAmps.jpg



127.8 Volts multiplied by 3.7 Amps equals 472.86 Watts.



4. Measure max Amps of system during Furmark benchmark.


FurmarkPSUtest.jpg


FurmarkAmps.jpg




127.8 Volts multiplied by 4.7 Amps equals 600.66 Watts.



5. Measure max Amps of system during 3dMark11 benchmark.


3dmark11PSUtest.jpg

3dMark11 score link: http://www.3dmark.com/3dm11/7457007

3dmark11Amps.jpg



127.8 Volts multiplied by 3.6 amps equals 460.08 Watts.




6. Measure max Amps of system during Firestrike Xtreme benchmark.


FirestrikePSUtest.jpg

FireStrike Xtreme score link: http://www.3dmark.com/3dm/1589101?


FirestrikeAmps.jpg



127.8 Volts multiplied by 3.6 amps equals 460.08 Watts.




Conclusion

My PSU is enough to handle my max load seen under Furmark benchmark of 600.66 AC Watts I would feel better having a high quality 750W PSU and that is what I would get from day 1 if I had the choice. For now my 660W is good enough.


Things to consider

During my tests I measured the AC side load which is normally higher than the actual DC output that a PSU is rated for. My Seasonic Platinum 660XP is rated for 660 DC Watts at around 90% efficiency. The AC WATT output equivalent would be 660 DC Watts x 90% of AC Watt efficiency = 660 DC Watts divided by 100 multiplied by 110 = 726 AC Watts.

Kind of confusing figuring out the AC Watts to DC Watts and the efficiency rating but I think this is it.

Ultimately the AC Watt is superior because that is what your utility company will bill you on.

Lastly my highest load of 600.66 AC Watts with Furmark is an oddly high load. For regular gaming I doubt any game will create this high of load. The main reason I run furmark is to test my cooling methods because it heats up the GPU so much.
 
Last edited:

That's_Corporate

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Now THIS is what I call an informative and helpful thread.
Unlike so many threads these days.

Utmost kudos to you, sir!
 

suiken_2mieu

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Great write up. What's your system load without the card? I'm trying to figure out what I need for 2 cards on my own system.
 

Gumbi10

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Hi Sonda, what kind of settings are you using to get 4.8ghz on your 4770k? Have you tweaked any other settings besides vcore, cos Haswell can see huge gains (regarding lower vcore) from tweaking vrin etc. I have my own 4770k at 4.5ghz at 1.29vcore 1.79 vrin.
 

Quartz-1

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I find it amazing your system uses so much power when idling.

Your figures are missing an important final step: you need to reduce the PSU requirement by its efficiency. Your max power input is 600W but if your PSU is only 80% efficient, only 480W is getting into your PC so you'd only need a 480W PSU.

Your 750W PSU has plenty of headroom - at 80% efficiency, you'd have to be drawing over 900W from the socket before there was a problem.
 
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cybereality

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Thanks for doing this. I feel a lot better.

Was considering a purchase of a 290/290x but I found out my 500W PSU was not enough.
 

SonDa5

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I find it amazing your system uses so much power when idling.

Your figures are missing an important final step: you need to reduce the PSU requirement by its efficiency. Your max power input is 600W but if your PSU is only 80% efficient, only 480W is getting into your PC so you'd only need a 480W PSU.

Your 750W PSU has plenty of headroom - at 80% efficiency, you'd have to be drawing over 900W from the socket before there was a problem.


First off I didn't measure Idling load. The lowest load I had was with light WEB surfing and youtube.

Also keep in mind I have that 5 channel by 30W fan controller maxed out and that water pump maxed out. Also my video card and CPU are over clocked with higher clocks and voltage than most systems.

At the conclusion of my tests I covered the AC WATT and DC Watt differences on the rating of the PSU. Also I stated that I used a Seasonic Platinum 660W PSU that is rated to be 90% efficient.
 
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SonDa5

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Hi Sonda, what kind of settings are you using to get 4.8ghz on your 4770k? Have you tweaked any other settings besides vcore, cos Haswell can see huge gains (regarding lower vcore) from tweaking vrin etc. I have my own 4770k at 4.5ghz at 1.29vcore 1.79 vrin.



All I did was set the clocks in Turbo mode up to 48 and increase vcore to 1.46v.
 

SonDa5

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Great write up. What's your system load without the card? I'm trying to figure out what I need for 2 cards on my own system.


I think a Seasonic Platinum 1000W PSU could handle the job. I don't think another card would add more than 400 WATTs even with a nice over clock.
 

sk3tch

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I think a Seasonic Platinum 1000W PSU could handle the job. I don't think another card would add more than 400 WATTs even with a nice over clock.

I've posted in other threads about this - but I have run 2x 290X OC'd along with an i5 2500K @ 4.6 GHz on my Lepa G900 (900W) PSU with no issues.

BTW SonDa5 - great write-up.
 

collegeboy69us

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I've posted in other threads about this - but I have run 2x 290X OC'd along with an i5 2500K @ 4.6 GHz on my Lepa G900 (900W) PSU with no issues.

BTW SonDa5 - great write-up.

this gives me hope -- I have a Corsair AX850 gold rated PSU and ultimate goal is to have two 290's (non X) mildy OC'd in the sytem. (running an OC'd 2500K as well)
 

magoo

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I think a Seasonic Platinum 1000W PSU could handle the job. I don't think another card would add more than 400 WATTs even with a nice over clock.

I have a Corsair AX 850W that is only 4 months old.
I'm no longer in need of it.
Full retail kit.

Give me a holler if you'd consider it.

Good unit, quiet. Has a very compact footprint, fully modular. I needed more power so I just got a Seasonic 1050X Gold.
 

magoo

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this gives me hope -- I have a Corsair AX850 gold rated PSU and ultimate goal is to have two 290's (non X) mildy OC'd in the sytem. (running an OC'd 2500K as well)

It can be done, but you'll pull almost 700W in Crossfire BEFORE you OC the cards.

I have two 290Xs, I had to move up a notch or burn the house down.:eek:
 

Wildace

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im using about 1120-1200 watts from the wall right now with the following,
4.4ghz AMD 8120
asus crosshair V
290 stock
7950 stock
7950 @ 1050core 1500 mem
4x 640GB WD black HDD Raid 0
2x 120GB Vertex 3 SSD's Raid 0
mouse, keyboard, track ir
h100 with 4 fans, push/pull,
7x 120mm case fans

thats with no real load on the cpu while litecoin mining and when im not using the pc for gaming.

i use the 290 for gaming when im actually at the pc.

i have a second 290 coming which will be here tuesday. depending on the power draw of the second one i might remove both 7950's from the case.
 

SonDa5

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Pushing at 4.9GHZ on 4770k and 1300/1600+ mhz on 290x and I think my Seasonic Platinum 660W is unable to keep up with power load requirements. The exhaust coming out from the PSU feels hot and my video output on my display cuts out and some time my system crashes on benches.

Either I am pushing the limits of my RIG or my PSU is unstable for the load. Will re-amp with higher clocks and post results soon.

OsJur ran into PSU power output problem with his highly over clocked RIG.

Well my meter is saying 740w from the socket with those clocks. So with 85% efficiency that would be 630w.
If I up the volts so that I can pass 1330mhz, my psu just shuts down.

So I need to lower my cpu clock and volts a lot before I can actually pass 1330mhz.
http://hardforum.com/showpost.php?p=1040389478&postcount=77
 
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