550W PSU sufficient for a HD4870?

[Fish_Fry]

As the title says, would a 550W PSU be sufficient for a 512mb 4870?

 

[Kkkk1]

I think on the box it states 550W as minimum. Personally I wouldn't go with the minimum as your poor old PSU is gonna be sweating it's nuts off. By the time you've taken the CPU, HD's and DVD roms etc I think you will be struggling. Even if it does cope with it you might not be getting it's best performance. However if you're already running this card on 550W continue to do so. Just be ready to replace it at some point.

 

[nerdnic]

What PSU do you have? I have a friend running a 4870 on a Corsair 550w and it works fine.

 

[Fish_Fry]

What PSU do you have? I have a friend running a 4870 on a Corsair 550w and it works fine.

I haven't got one yet, but the one that will come with my system is this: http://www.hardware.info/en-US/productdb/bGNkZ5iZmJPK/viewproduct/LC_Power_Silent_Giant_550W/

Would that suffice?

 

[nerdnic]

It drops to 67% efficiency when using 340 watts, which is where you will be sitting under load. It has decent 12v rails, but only one pci-e 6pin. (4870 needs 2)

I suppose you could use an adapter for the other pci-e, but I would recommend that you upgrade the PSU. It will probably run it, but I would not count on it being a permanent solution.

 

[nerdnic]

Here are 3 suggestions:

http://www.newegg.com/Product/Product.aspx?Item=N82E16817371007
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139004
http://www.newegg.com/Product/Product.aspx?Item=N82E16817703005

 

[aevm]

Yuck. That so-called 550W LC6550 PSU has a maximum combined rating of 24A on the 12V rails. Compare that with the Corsair 550VX at 41A. I wouldn't try it.


Edit: +1 for nerdnic's suggestions.all good.
If you're getting a Crossfire motherboard you should get a Corsair 650TX, that can handle two HD 4870 cards.

 

[nerdnic]

Yuck. That so-called 550W PSU has a maximum combined rating of 24A on the 12V rails. Compare that with the Corsair 550VX at 41A. I wouldn't try it.

Quoted power
Continuous power 550 W
Max. current 12 V - Rail 1 16 A
Max. current 12 V - Rail 2 18 A

 

[aevm]

Yeah, it looks good on paper with 16+18A. But you can't just add the rails up, except for a couple of models like Earthwatts for example. Here's a list:
http://forums.guru3d.com/showthread.php?t=205763

 

[nerdnic]

The actual power consumption of the GPU is not that great. A dedicated 16 or 18 rail is plenty for a GPU.

Edit:
I don't think the PSU is up to snuff, but power requirements are blown out of proportion most of the time. The actual needed power is a lot less, granted you have a decent PSU.

 

[kpo6969]

As the title says, would a 550W PSU be sufficient for a 512mb 4870?

http://www.buy.com/prod/corsair-650w-tx-series-80-plus-certified-power-supply-corsair-tx-cmpsu/q/loc/101/206178324.html
or a little leeway:
http://www.buy.com/prod/corsair-750w-tx-series-80-plus-certified-power-supply-corsair-tx-cmpsu/q/loc/101/206178325.html

The actual power consumption of the GPU is not that great. A dedicated 16 or 18 rail is plenty for a GPU.

Edit:
I don't think the PSU is up to snuff, but power requirements are blown out of proportion most of the time. The actual needed power is a lot less, granted you have a decent PSU.

 

[nukemaster]

That PSU is designed in an older/cheap manner. Modern PSU's can dedicate a large portion of there power to the 12 volt lines.

Will it work, i would guess so, but i have never used that psu and not all psu;s are created equally.

Just some quick figures on my system

OS: Vista Home Premium 64-bit
Case: Antec 900
PSU: OCZ 700watt
Board: P35 DS3R
CPU: Q6600 @ 3.00
CPU cooling : Zalman 9500 @ 500-2200 rpms(PWM)
Memory: 4x 2048MB @ 4,4,4,10 (800)
Video: HD 4870
Storage:
2x WDC 250gig (Raid0)
2x Seagate 320gig(Storage)
Optical drive: Pioneer DVR-115DBK
KB/Mouse: Logitech Access 600, G9 Mouse
Sound: Creative SB Audigy 2zs

180-185 idle
Aero move windows 188-190
No Aero move windows 220-224 - No restart, may need a restart to work better
220-250 COH(City Of Heroes)
260 Prime94
280-300 UT3
340-346 Prime + Furmarks
361 PEAK

 

[Primus462]

I have an Antec NeoPower 500 and it works fine with my 4870. I have the 4870 Oced and I have my 5000+ BE OCed to 3.15Ghz. I have never had any problems. I would say the 500w PSU would suffice, but if you have a little extra cash, it never hurts to go bigger. If you plan on keeping buying a PSU to use for a couple of years, then the extra watts couldn't hurt.