# Just what kind of power supply do I really need for a Radeon 4850?
**URL:** https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161
**Category:** Factual Questions
**Created:** [April 15, 2010, 3:07am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161 "2010-04-15T03:07:58Z")
**Posts on this page:** 9
**Page:** 1
### Author:  [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)
#### Post date: [April 15, 2010, 3:07am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/1 "2010-04-15T03:07:58Z")
I’ve got my new PC, and due to a funny case design I can’t use the 450 watt power supply I was planning on. That power supply had an unusually short distance between SATA connecters and it won’t go reach far enough to plug into the dvd drive and the hard drive at once.
Yes, I can and will get another if neccesary.
However, it occurs to me I might be able to use a different option. Why shouldn’t a 400 Watt power supply work? I really doubt the graphics card actually pulls down 100+ watts even in heavy use. Sure, it’s “recommended,” but ain’t that a little way of covering their butts and avoiding complaints on the poeple who have fifty different plugins? I checked Tom’s hardware on a different OEM model of the same card, and that suggested there was no way the combined unit would pull over 400 watts to me.
And let’s say I mosey over to ATI’s little shop and pick out a “recommended” power supply. What exactly does this mean? That the manufacturing kicks some cash back to ATI? Also, for practical reasons I would prefer to have a normal-size (lengthwise) power supply - and I think a 40 watt power supply I’m looking at will do nicely. It will improve airflow and cable management.\
So, any opinions?
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### Author:  [@yoyodyne](https://boards.straightdope.com/u/yoyodyne)
#### Post date: [April 15, 2010, 3:18am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/2 "2010-04-15T03:18:49Z")
If you get a quality 400W (particularly one with a single 12V rail) you shouldn’t have a problem. If you do however, it may be difficult to diagnose. The price difference in the 400 - 600 watt range aren’t worth taking the chance to me, YMMV.
You could use a 4-pin molex to SATA adapter/extension to power one of the drives using the current supply.
If you get a different PS I recommend one with modular cables.
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### Author:  [@yoyodyne](https://boards.straightdope.com/u/yoyodyne)
#### Post date: [April 15, 2010, 3:39am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/3 "2010-04-15T03:39:30Z")
[Here are some cables](http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=2010010001%20117752938&bop=And&ShowDeactivatedMark=False&SrchInDesc=sata&Page=1) to lengthen the SATA connector, both 4-pin to SATA and SATA to SATA.
If I were to get a new PS it would probably be [this one](http://www.newegg.com/Product/Product.aspx?Item=N82E16817171036).
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### Author:  [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)
#### Post date: [April 15, 2010, 4:33am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/4 "2010-04-15T04:33:30Z")
Unless you’re running dual video cards or a 10-drive RAID or something, 400w is plenty. Assuming it’s a decent psu that can deliver its rated wattage. Cable extenders and adapters should be cheap.
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### Author:  [@ZipperJJ](https://boards.straightdope.com/u/ZipperJJ)
#### Post date: [April 15, 2010, 6:00am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/5 "2010-04-15T06:00:04Z")
When I was building my wish list for my new build, I was surprised when [Newegg’s PSU calculator](http://educations.newegg.com/tool/psucalc/index.html) told me ~430W would do. It’s a handy tool.
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### Author:  [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)
#### Post date: [April 16, 2010, 12:03am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/6 "2010-04-16T00:03:08Z")
Thank you all for the help. The unit has a single 75 watt power input - so that’s the maximum increase I should need in any case (over what I already have) right?
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### Author:  [@smiling\_bandit](https://boards.straightdope.com/u/smiling_bandit)
#### Post date: [April 16, 2010, 12:09am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/7 "2010-04-16T00:09:40Z")
Update:
Thank you all for the help. The unit has a single 75 watt power input - so that’s the maximum increase I should need in any case (over what I already have) right? The automatic thing popped up by Newegg’s link says it goes up from 284 to 401 watts.
Edit: how can I know which ones are good power supplies? The prices on newegg, on what their links bring up, range from 15 bucks much, much more?
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### Author:  [@Dag\_Otto](https://boards.straightdope.com/u/Dag_Otto)
#### Post date: [April 16, 2010, 4:05am UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/8 "2010-04-16T04:05:56Z")
Best bet, look at the user reviews on places like newegg - the reliable PS will have better reviews. Even great products will have a few lemons, but the really good products will have hundreds of reviews. If a product had hundreds of reviews and is 4 eggs or better, then it’s a pretty safe bet.
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### Author:  [@yoyodyne](https://boards.straightdope.com/u/yoyodyne)
#### Post date: [April 16, 2010, 12:59pm UTC](https://boards.straightdope.com/t/just-what-kind-of-power-supply-do-i-really-need-for-a-radeon-4850/536161/9 "2010-04-16T12:59:21Z")
Another tip: the PS is important and not a part you want to go with the cheapest.