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Resolved Question

Power supply considerations re new Graphics card

by Dec 1, 2013 7:01PM PST

Hi all

Please can you advise me on this:

I am upgrading my graphics card. Currently I still have the card bundled with my PC - Nvidia GT 630, a low end card.

I want to replace it with a 2 Gb ASUS HD7850. See here:

http://www.pcworld.co.uk/gbuk/components-upgrades/graphics-cards/graphics-cards/asus-hd7850-dc2t-2gd5-v2-pci-e-3-0-graphics-card-19464033-pdt.html

Are there any checks I should do, to see if my power supply is adequate enough for this new card?

I can I check what model / size of power supply is in my machine currently?

From the link, it says:

"Power consumption up to 150W 1 additional 6 pin PCIe power required"

This seems to suggest some modification is needed to the power supply?

Thanks for any advice.

For info my machine is a Lenovo, I dont remember the exact model, but its only a year old (Intel Quad Core i5 and 8Gb RAM) so reasonably modern.

Discussion is locked

GAW1903 has chosen the best answer to their question. View answer
6 Posts
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Best Answer

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Psu
by Dec 1, 2013 11:45PM PST
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thanks
by GAW1903 Dec 1, 2013 11:58PM PST
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Answer
A little math.
by Forum moderator Dec 1, 2013 11:42PM PST

150 Watts at 12 Volts is 12.5 Amperes. To stay out of trouble you keep the power supply under 50% of it's maximum output.

For me I use a P3 Watt meter on the system to find it's total draw. Now I double that, add 300 and that gives me the total Watts I want to see on the PSU.

One last check is the Amperes on the +12V rail. Since this card tops out at 12.5 Amperes and there are other things in the machine that use this, let's triple that and look for a 37.5 Ampere or better 12 Volt rail.

Bob

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One more Q
by GAW1903 Dec 1, 2013 11:56PM PST
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- how do you check what Ampere rating the +12v rail has?
by r. proffitt Forum moderator Dec 2, 2013 12:04AM PST

I read the label on the side of the PSU. (sorry but that is how I check.)

Yes you could check the specs on it on the web but many models don't have specs on the web. Your link didn't have that so you head to the maker's web page to check it out.
Bob

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Search around, that's not a power and quality to price PSU
by HurricaneBacon Dec 6, 2013 5:05AM PST
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