Too much for my psu???

[stevie44]

I wanted to get some feedback on replacing my gpu with the Gigabyte HD 6850, which is on newegg for $139.00. Having little knowledge about how specs go, only difference from my 6770 is the 6850 is 256 bit. But clock speed and memory clock or very close to the same. Question is the psu stats. Extreme psu calc shows me at minimum of 369 and 419 recommended. As shows on newegg the 6850 tells me 500 watt psu. My xfx 6770 also suggested this 500 watt psu, but runs with no issues almost a year now. But yes no the same gpu's either. I've read forums for few days now, even one gamer saying he has a dell with 350 watt psu and runs the 6850 on it. Sites shows the Gigabyte pulls 127 watts from the system. Any help or suggestions would be greatful for this noob.....steve


PC specs: Phenom II 955 BE 3.2ghz
4 sticks of DDR2 800
Western Digital HD regular Sata
DVD RW drive
pci nic card
XFX 6770 1gb gpu(currently, but fan blade broken and very noisy)
2 fans, one on cpu and other on back of case.


psu stats from Antec
EA 430
430 Watt Continuous Power:


+5V
20.0A
±5％
36A
50

+12V1
17.0A
±5％
22A
120

+12V2
16.0A
±5％
22A
120

-12V
0.8A
±10％
120

+5VSB
2.5A
±5％
50

+3.3V
20.0A
±5％
31A
50

 

[1337RPG]

Im pretty sure the 430watts will be enough even when your cpu and gpu are on full load. The PSU requirements on the box are higher than you actually need. I'm using a 6570 thats slightly overclocked and my power supply is only 200w, even thought the 6570 box says at least 400w.

 

[bigcyco1]

The specs in your post with a 6850 included will have a hard time draining 430 watts i think so you should be fine let others confirm this first though lol

 

[Sakkura]

Yeah it should be enough. I ran my 6850 on a 430W PSU, though that was with a core 2 duo so it isn't directly comparable to your system.

You shouldn't go much higher though. Perhaps a 7850 because it's also pretty frugal (almost exactly the same TDP, and total system power draw only barely edged over 250W in Metro 2033 with an overclocked Core i7 in Tom's review).

 

[bigcyco1]

Check here i would do it but i am off to eat http://www.tomshardware.co.uk/forum/314712-10-please-read-determine-power-required The chart here will tell you how much power your GPU(s) need: http://forums.atomicmpc.com.au/index.php?showtopic=264

 

[egilbe]

22 amps on two rails= 44 amps*12volts=528watts. Since Antec is a good PSU company, they rate their PSU's lower than some companies. It makes them last longer. It's why I never look at the manufacturers rated wattage and figure my own calculations. Some companies even add the amps used on the 5volt and 3.3volt rails to boost the rated wattage up!

 

[Onus]

A 430W Antec Earthwatts will have no difficulty at all with a HD6850; none. The most any [stock] graphics card with a single PCIe power connector can possibly draw is 150W (75 for the PCIe slot and 75W for the single 6-pin connector). You'll be fine.

 

[Sakkura]

22 amps on two rails= 44 amps*12volts=528watts. Since Antec is a good PSU company, they rate their PSU's lower than some companies. It makes them last longer. It's why I never look at the manufacturers rated wattage and figure my own calculations. Some companies even add the amps used on the 5volt and 3.3volt rails to boost the rated wattage up!

Those are the maximum amps for each 12V rail individually, but in total they can only supply up to 360W (30 amps). Still enough for a 6850 though. The higher amps on each 12V rail just provides more flexibility, so you don't "lose" watts/amps by not utilizing the full capacity of one rail.

Edit: Also, the true max amps for the two 12V rails are actually 17 and 16.

 

[stevie44]

A 430W Antec Earthwatts will have no difficulty at all with a HD6850; none. The most any [stock] graphics card with a single PCIe power connector can possibly draw is 150W (75 for the PCIe slot and 75W for the single 6-pin connector). You'll be fine.

So sites like xtreme calculator, that give me numbers like 379 min and 419 recommended. Those numbers are at "max load". I'm not planning on overclocking or adding more to the power draw, till can get better psu. Looking at some Corsair and Antec in the 650 watt.

 

[stevie44]

Best answer selected by stevie44.