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Power supply for HD3850

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dpapag

Member
Joined
Aug 30, 2002
Location
Southern USA
What power supply should I get for the following setup:

Athlon XP 2500 mobile barton overclocked to 2.4Ghz
Abit NF7s v1.2
2x1 GB OZC PC3200
HD3850 AGP 512MB

I found what ati lists as power supplies that will work for the HD3850 here:

http://ati.amd.com/products/certified/powersupplies.html#pstop

I currently have an enermax 350w EG 365P-VE that is not on the list.

Output: +3.3V @ 32A; +5V @ 32A; +12V1 @ 26A; -12V @ 1A; +5VSB@ 2.2A

Do I need to upgrade? If so, is the Corsair HX520W 520W the way to go?
 
What power supply should I get for the following setup:

Athlon XP 2500 mobile barton overclocked to 2.4Ghz
Abit NF7s v1.2
2x1 GB OZC PC3200
HD3850 AGP 512MB

I found what ati lists as power supplies that will work for the HD3850 here:

http://ati.amd.com/products/certified/powersupplies.html#pstop

I currently have an enermax 350w EG 365P-VE that is not on the list.

Output: +3.3V @ 32A; +5V @ 32A; +12V1 @ 26A; -12V @ 1A; +5VSB@ 2.2A

Do I need to upgrade? If so, is the Corsair HX520W 520W the way to go?

DP,

Corsair 400CX 400w or VX450 will do it easily for a single 3850 unless you're set on a modular.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139008
 
I would dare to say your are OK with that PSU , as long as u have an 8 pin connector, but if its old it be better to get a new one just in case .
 
I would dare to say your are OK with that PSU , as long as u have an 8 pin connector, but if its old it be better to get a new one just in case .

Charlie,

I think the 3850 and 3870 are 6 pin PCIe connector?
 
Alot of AGP versions have 8 pin plugs , this is because AGP slot can't deliver enought to the card , 6 pin does 75 watts , when 8 pin does 150 watts , power requirements of the card is 95 watts maximum ( it is alot less , but i think thats an official number ) . But i also think it might work with 6 pin , am not however very sure of that .But yes there were also cards with 6 pin plugs .
 
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Alot of AGP versions have 8 pin plugs , this is because AGP slot can't deliver enought to the card , 6 pin does 75 watts , when 8 pin does 150 watts , power requirements of the card is 95 watts maximum ( it is alot less , but i think thats an official number ) . But i also think it might work with 6 pin , am not however very sure of that .

Charlie,

You're correct. The AGP versions seem to be mixed 6 pin and 8 pin depending on the brand.
 
The vid card has an 8 pin female which attaches to the card itself, and it has two white 4 pin molex connectors to attach to the power supply. (only 3 pins are present in each)

Vid Card

The 350w enermax that I have looks like this (one on the right)

cables.jpg

Which line should I hook the vid card to? The second set of wires from the left, or does it not matter? I think the 2nd to last set of wires from the right has an 8 pin on it. Does that go directly to the vid card instead of using the supplied 8pin-molex adapter?
 
Use a native 8 pin if you have one , most manufactures have dedicated rail for the PCI-e connector.
 
DP,

Corsair 400CX 400w or VX450 will do it easily for a single 3850 unless you're set on a modular.

http://www.newegg.com/Product/Product.aspx?Item=N82E16817139008

I picked up that Corsair for $40.
Looking at the specs it has a single 12v rail that puts out 30a

It also has the PCIe adapter that is a 6 pin, but it doesn't say how many amps is on that rail. I'm guessing 16-18? I have a 6 pin to 8 pin adapter.

Which method of hook up is more stable?

1. Use the 6 to 8 pin PCIe adapter and hook the card up that way.
2. Use the HD3850 enclosed 8 pin to (two) 4 pin molex adapter, but only hook up one of the 4 pin molex to the 12v rail, as that should be plenty and the power supply only has a single 12v rail @ 30a.

I'd like to use option 1, as that will leave me with more 4 pin molex connectors which I need for my case fans. I can go with option 2, but then I'll have to use these: HERE to get the fans to work.
 
Thanks. Vid card seems to be working fine. The mobo has a 20 pin ATXPWR1 connector and a 4 pin ATX12V1. Manual says that general designed ATX power supplies do not have a ATX12V1 connector provided, so there's no need to connect anything to the ATX12c1 connector.

I currently have just the 20 pin from the mobo plugged into the Corsair PSU using the adapter and it seems to be working fine. Being that the PSU DOES have a 4 pin connector, do I need to plug that into the ATX12V1 slot on the mobo as well? The last gauge on MBM 5 is showing 3.55v for the -5v gauge! What does that mean? All the other voltages appear to be fine.
 
Take no notice of the -5 reading. Most software gets this wrong. You should plug the 4-pin lead into the ATX12V1 slot, This normally gives your CPU a more stable power supply.
 
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