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What Power Supply to get

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August 15, 2012 1:45:36 AM

Hi, I've spent a while now looking at components for my first custom build and I'm pretty confident that I'm ready to order them. However in addition to going a bit over budget, the additional price of monitor and OS has added up and the total price is now sitting quite high, (higher than my parents would like I think) and I've been looking at ways of getting it down without compromising too much on my specs.

What I noticed is that the case I'm buying (for £30) comes with a free power supply of 450W. The power supply I've been looking at (for about £50) is 600W. Is the difference in value between the two power supplies merely due to the 150W difference, or is there some difference in quality as well? I remember reading somewhere that it's better to go with a more expensive power supply because if it breaks it can potentially be dangerous for your computer's components, so I'm not sure whether I would want to go for one that comes free with a £30 case in any case(*ahem*).
Obviously the upgrading opportunities with a 600W power supply are to be considered but if my system fit comfortably under 450W and I didn't plan to upgrade beyond that, is it worth dropping the expensive power supply and going for that one? If I do need to upgrade I could invest in a new power supply later, and I wouldn't have lost much since the power supply came free with the case. Unless of course the power supply had damaged some of my components somehow, in which case I would have lost much.

I suppose what I'm asking is, will a cheap (or free, rather) power supply endanger my computer components, or am I being overly paranoid based on what one random guy said about the dangers of crappy power supplies?
Here's links to the power supply I've been considering buying, and the case that comes free with one: (respectively)

http://www.cclonline.com/product/18316/OCZ600MXSP-UK/Po...

http://www.cclonline.com/product/3760/2720D/Cases/Galax...

Thanks :) 

More about : power supply

a b B Homebuilt system
a b ) Power supply
August 15, 2012 2:11:42 AM

You would be correct in assuming that more expensive PSUs are generally better.

The 3-4 numbers that manufacturers tack on to the PSU model don't mean much at all. Two different PSUs that are both marketed at 500 watts can have drastically different performance characteristics.

For example, good PSUs from SeaSonic will usually deliver 90% of their marketed value on the 12 volt rail alone with plenty on the 3.3 volt and 5 volt rails. All 3 rails combined can add up to over 800 watts but the rated output for stability and lifespan is 500 watts. Good PSUs will always deliver their rated capacity and usually more. Cheaper PSUs will have half their rated capacity on the 12 volt rail or less. They often have excessive power on the 3.3 volt and 5 volt rails where it is not only easier to deliver, but will never be used. They often market the cheap PSUs as the combined load on all 3 rails even if this combined value cannot be obtained without destroying the power supply. Yes, many PSUs are a false advertising case in the making.

Anyway, the OCZ ModStream lineup is kinda 'meh'. Not horrible, but not great by any means. There are far better PSUs in the same price range. For a good roundup visit http://www.hardocp.com/
a c 84 B Homebuilt system
a c 143 ) Power supply
August 15, 2012 2:12:51 AM

The ONLY case vendor that includes a PSU that I would trust is Antec.
A cheap psu will not deliver the wattage it claims, will not deliver it above room temperature, and if it fails, can damage anything it is connected to. A cheap case is ok, and a good way to save if you must.

A psu is the LAST place to go buy cheap on a build.

Could you list the other parts of your build, along with some links?
Perhaps we can find a way to reduce your costs.
Is your primary use for gaming?

It is the graphics card that determines how much amperage you need(not wattage)
Related resources
a c 82 B Homebuilt system
a c 261 ) Power supply
August 15, 2012 2:23:48 AM

Most power supplies that come with cases are crap plain and simple. They are made by companies that cut corners during manuacturing and very rarely can even output the power they are rated at. Even 2 "name brand" companies that sell great cases and cooling accessories, Coolermaster and Thermaltake are not companies that do power supplies well. A small percentage of their units are good quality while the vast majority including the ones that come with their cases are junk.

The power supply is the most important part of a computer. If you don't have a stable power supply you don't have a stable computer. At the worst a bad power supply can actually damage or even destroy your components.

There are plenty of excellent power supplies that don't cost an arm and a leg. The OCZ you linked to is a very good model. The companies I trust across the board are Corsair, Seasonic, PC Power and Cooling, XFX, Silverstone, Enermax, OCZ and Antec.

Here is a list of power required by a system with pretty much every graphics card. Remember this is for the whole system not just the card.

http://www.realhardtechx.com/index_archivos/Page362.htm
August 15, 2012 4:00:17 AM

Pinhedd said:
You would be correct in assuming that more expensive PSUs are generally better.

The 3-4 numbers that manufacturers tack on to the PSU model don't mean much at all. Two different PSUs that are both marketed at 500 watts can have drastically different performance characteristics.

For example, good PSUs from SeaSonic will usually deliver 90% of their marketed value on the 12 volt rail alone with plenty on the 3.3 volt and 5 volt rails. All 3 rails combined can add up to over 800 watts but the rated output for stability and lifespan is 500 watts. Good PSUs will always deliver their rated capacity and usually more. Cheaper PSUs will have half their rated capacity on the 12 volt rail or less. They often have excessive power on the 3.3 volt and 5 volt rails where it is not only easier to deliver, but will never be used. They often market the cheap PSUs as the combined load on all 3 rails even if this combined value cannot be obtained without destroying the power supply. Yes, many PSUs are a false advertising case in the making.

Anyway, the OCZ ModStream lineup is kinda 'meh'. Not horrible, but not great by any means. There are far better PSUs in the same price range. For a good roundup visit http://www.hardocp.com/


Thanks, that clears up a lot. I'll know to definitely avoid cheap PSUs. I'll maybe look at other PSUs before I order anything, too.

Quote:
Most power supplies that come with cases are crap plain and simple. They are made by companies that cut corners during manuacturing and very rarely can even output the power they are rated at. Even 2 "name brand" companies that sell great cases and cooling accessories, Coolermaster and Thermaltake are not companies that do power supplies well. A small percentage of their units are good quality while the vast majority including the ones that come with their cases are junk.

The power supply is the most important part of a computer. If you don't have a stable power supply you don't have a stable computer. At the worst a bad power supply can actually damage or even destroy your components.

There are plenty of excellent power supplies that don't cost an arm and a leg. The OCZ you linked to is a very good model. The companies I trust across the board are Corsair, Seasonic, PC Power and Cooling, XFX, Silverstone, Enermax, OCZ and Antec.

Here is a list of power required by a system with pretty much every graphics card. Remember this is for the whole system not just the card.

http://www.realhardtechx.com/index [...] age362.htm


Yeah, I guessed as much. I'm pretty sure my system would easily fit the 600W PSU even with upgrades in terms of wattage, but considering how inaccurate the supposed wattage of the free 450W PSU is, I definitely wouldn't trust it when my system isn't that far under it.

Quote:
The ONLY case vendor that includes a PSU that I would trust is Antec.
A cheap psu will not deliver the wattage it claims, will not deliver it above room temperature, and if it fails, can damage anything it is connected to. A cheap case is ok, and a good way to save if you must.

A psu is the LAST place to go buy cheap on a build.

Could you list the other parts of your build, along with some links?
Perhaps we can find a way to reduce your costs.
Is your primary use for gaming?

It is the graphics card that determines how much amperage you need(not wattage)


Here's the stuff I've been looking at:

Spoiler
Motherboard
Asus M5A97 Motherboard 90-MIBFS0-G0AAY00Z
£69.65
http://www.cclonline.com/product/7 [...] d/MBD0327/

CPU
AMD Phenom II X4 965 Black Edition 3.4GHz Quad Core Processor HDZ965FBGMBOX
£87.73
http://www.cclonline.com/product/2 [...] r/CPU1046/

Graphics Card
XFX Radeon HD 7750 Graphics Card 1GB FX-775A-ZDB4
£91.72
http://www.cclonline.com/product/8 [...] B/VGA0606/

Memory
4GB Corsair XMS3 1333MHz DDR3 Dual Channel Memory Kit TW3X4G1333C9A
£25.16
http://www.cclonline.com/product/3 [...] t/RAM5965/

Wireless Card
TP Link TL-WN881ND 300Mbps Wireless N PCI Express Adapter TL-WN881ND
£16.63
http://www.cclonline.com/product/7 [...] r/NET0394/

Power Supply
600W OCZ ModXStream Pro Modular Power Supply OCZ600MXSP-UK
£56.70
http://www.cclonline.com/product/1 [...] y/PSU1077/

Hard Drive
Western Digital Caviar Blue 500GB (7200rpm) SATA 6Gb/s 16MB 3.5 inch Hard Drive WD5000AAKX
£48.78
http://www.cclonline.com/product/4 [...] e/HDD1106/

DVD Drive
Sony 24x Internal DVDRW Drive AD-5280S-0B
£17.89
http://www.cclonline.com/product/7 [...] e/CDR0118/

Case
Galaxy III Black 2720D
£36.25
http://www.cclonline.com/product/3 [...] k/CAS0119/

Monitor
Acer V223HQVbd 22" TFT Monitor ET.WV3HE.021
£79.99
http://www.cclonline.com/product/6 [...] r/MON0496/

Keyboard
CiT KB-2106C USB/PS2 Combo Keyboard KB-2106C
£5.21
http://www.cclonline.com/product/7 [...] d/KBD0426/

Mouse
Logitech M100 Corded Optical Mouse 910-001602
£11.23
http://www.cclonline.com/product/4 [...] e/MOU1287/


It all comes to £617.58, including Windows 7 64 Bit for £70.34

Also, I've looked at the PSU and GPU's pages and can't find anything about the amperage...
August 15, 2012 4:03:14 AM

Also, forgot to mention: yeah, the main use will be gaming. (sorry for the double post but apparently I'm not allowed to edit...)
a c 82 B Homebuilt system
a c 261 ) Power supply
August 15, 2012 5:04:35 AM

An HD 7750 only needs a recommended 350w power supply. If you are set on that system then this is a great choice and it's cheap.

http://www.cclonline.com/product/55295/CMPSU-430CXUK/Po...

Edit: Actually that works out to about $60 US. That's crazy expensive for what you can get it for here in the states. Almost double. I'm not sure if your prices are just higher or you might find it cheaper elsewhere.

In fact it's only $25 after rebates right now here.

http://www.newegg.com/Product/Product.aspx?Item=N82E168...
August 15, 2012 7:14:13 AM

I have an 800w PSU (corsair gs 800, witch costed 100 Euro) for a rated ..lets say in worst case 350- 400W consumption of my PC. Why did i purchase this PSU? many will consider it overkill, and if you do the math its kinda overkill, BUT i did take in mind that @ 50% load on thethis PSu the efficiency its higher then 90% witch is similar to gold certified PSUs, witch cost alot more then mine... The heat produced by this PSU its minimal considering that it runs @ max 50% load AND ofc, IF i want to SLI my card in the future (or get 2 new cards) i am able to do it without thinking about the PSU... So, either do a simple math of your power consumption of you PC and get a PSu that will get max 80% load with your speccs or you could go higher and get more efficiency and be more future proof.
a c 106 B Homebuilt system
a b ) Power supply
August 15, 2012 7:30:06 AM

Pinhedd said:
. Cheaper PSUs will have half their rated capacity on the 12 volt rail or less. They often have excessive power on the 3.3 volt and 5 volt rails where it is not only easier to deliver, but will never be used. They often market the cheap PSUs as the combined load on all 3 rails even if this combined value cannot be obtained without destroying the power supply. Yes, many PSUs are a false advertising case in the making.


I agree fully with this. I have a generic PSU laying around somewhere that claims 550W, only 230W on the 12v. They included the other rails to inflate the total wattage. Also being generic, you cant even trust the sticker to be accurate of its actual abilities. Generic or very cheap PSU's (as comes with cheap cases) are not to be trusted, they tend to die with a bang that will take the rest of the build with it. Don't even mention good efficiency, you wont find that either.

The OCZ Modstream is a decent unit, not what I would suggest (Corsair, XFX, etc. The usual recommendations), but it will perform adequately and wont blow up the rig.
a c 84 B Homebuilt system
a c 143 ) Power supply
August 15, 2012 2:32:24 PM

I think you can do better with your budget.
Since I am not conversant with UK prices, let me generalize a bit on how to allocate your budget.

1) For gaming, the graphics card is all important, more so than the cpu. My rule of thumb for a gaming pc is to spend twice your cpu budget on the graphics card. In your case, I suggest a less expensive dual core cpu and a stronger graphics card.

2) For gaming, unfortunately, there are NO amd cpu's that will compete with an intel chip at any price point, at least in the US.
Read this tom's article on the best cgaming cpu'ds for the money July 2012:
http://www.tomshardware.com/reviews/gaming-cpu-review-o...
For your budget, a dual core intel chip pared with a stronger graphics card will give you better gaming.
Read this article on <$200 gaming cpu's:
http://www.tomshardware.com/reviews/best-gaming-cpu-cor...

3) The 7750 is an ok card. It is the strongest card that will run without needing a psu with a 6 pin pcie power connector.
350W would do it. If you go stronger, a 450w-500w unit should do. It will usually have the required 6 pin connector, and better ones will have two. If you buy a more modern card that uses 28nm manufacturing process, the power requirements will be less. That would be the amd 7xxx series, or the Nvidia GTX6xxx.

4) For an intel cpu, any 1155 motherboard will do. Look at smaller form factors like M-atx, which are usually less expensive.

5) For the psu, buy only a quality unit. My short list would include Seasonic, PC P&C, Corsair, Antec, and XFX. OCZ quality can be iffy. The amperage delivered to all the +12v rails is the real metric. You will see this on the data plate of the psu. Sometimes, it is stated in watts for the 12v rails. To get amps, divide the watts by 12v.

Put together another list with this info and let's see if it looks better, and perhaps costs less.
a c 84 B Homebuilt system
a c 143 ) Power supply
August 15, 2012 2:37:48 PM

Cumb can't edit!
Look at the heirarchy list at the end of this article to get an idea of the relative strengths of different graphics cards. A difference of a couple of tiers is not that important.
http://www.tomshardware.com/reviews/gaming-graphics-car...
a c 84 B Homebuilt system
a c 143 ) Power supply
August 15, 2012 2:38:05 PM

Dumb!!!
August 15, 2012 7:20:23 PM

geofelt said:
I think you can do better with your budget.
Since I am not conversant with UK prices, let me generalize a bit on how to allocate your budget.

1) For gaming, the graphics card is all important, more so than the cpu. My rule of thumb for a gaming pc is to spend twice your cpu budget on the graphics card. In your case, I suggest a less expensive dual core cpu and a stronger graphics card.

2) For gaming, unfortunately, there are NO amd cpu's that will compete with an intel chip at any price point, at least in the US.
Read this tom's article on the best cgaming cpu'ds for the money July 2012:
http://www.tomshardware.com/reviews/gaming-cpu-review-o...
For your budget, a dual core intel chip pared with a stronger graphics card will give you better gaming.
Read this article on <$200 gaming cpu's:
http://www.tomshardware.com/reviews/best-gaming-cpu-cor...

3) The 7750 is an ok card. It is the strongest card that will run without needing a psu with a 6 pin pcie power connector.
350W would do it. If you go stronger, a 450w-500w unit should do. It will usually have the required 6 pin connector, and better ones will have two. If you buy a more modern card that uses 28nm manufacturing process, the power requirements will be less. That would be the amd 7xxx series, or the Nvidia GTX6xxx.

4) For an intel cpu, any 1155 motherboard will do. Look at smaller form factors like M-atx, which are usually less expensive.

5) For the psu, buy only a quality unit. My short list would include Seasonic, PC P&C, Corsair, Antec, and XFX. OCZ quality can be iffy. The amperage delivered to all the +12v rails is the real metric. You will see this on the data plate of the psu. Sometimes, it is stated in watts for the 12v rails. To get amps, divide the watts by 12v.

Put together another list with this info and let's see if it looks better, and perhaps costs less.


While gaming is the main focus of this computer, I occasionally do a bit of music creation and sometimes video editing as well so the benefits of a multi core CPU might be a bit more significant, especially if I get round to doing more music creation in the life of this next computer as I would like to do. It might not be enough to justify this particular CPU since I'm still not sure how important multi-threading is to music programs and I don't do it that often but it's worth considering, I think. I suppose I can always upgrade in the future if I do get more heavily involved with it. Still, I'll take your rule into account. I've been wondering about the ratio of value between GPUs and CPUs for a gaming rig so that will be helpful.

As for switching to Intel, I'm going to be stubborn and stick with AMD. I've been using AMD processors for a while now and most of my friends use AMD too, so I'll probably stay with them for the time being.

I'll look into some more PSUs, since the general response towards OCZ has been mixed. I'll compare the amperage this time, as well.
a c 82 B Homebuilt system
a c 261 ) Power supply
August 15, 2012 9:17:05 PM

The Corsair 430CX I linked to above is plenty for your computer and is very highly rated. It's cheaper than the OCZ as well.

The OCZ is an excellent power supply and anyone saying it's not is misinformed. If you just have your heart set on it for some reason then get it.

It get a Golden award from Hardwaresecrets. Their highest award.

http://www.hardwaresecrets.com/article/OCZ-ModXStream-P...
August 15, 2012 11:55:28 PM

Would the positive reviews include the CX500 as well?

http://www.cclonline.com/product/86908/CMPSU-500CXV2UK/...

I would rather get this 500W one since it's only £8 more and it leaves a bit more upgrade room. Also, on the GPU's page ( http://www.cclonline.com/product/81324/FX-775A-ZDB4/Gra... ) it says the minimum power supply requirement is 450W. Is this to trick people into buying more expensive PSUs than they need or just being overly cautious?

If the 500CX isn't as good as the 430CX for some reason, I suppose I could settle for 430W.
a c 82 B Homebuilt system
a c 261 ) Power supply
August 16, 2012 12:06:58 AM

No the 500CX is a great model as well. The 430 is plenty for your system though.

When AMD or Nvidia recommend a power supply size they have to base that on the fact that the vast majority of computers have generic power supplies. The brands in my above post are high quality and can actually output their rated voltage if not quite a bit more than they are rated for.

This list is fine to go by. I posted it above as well. This is the manufacturer recommended list. That website recommending 450 watts is just wrong or trying to make you spend money.

http://www.realhardtechx.com/index_archivos/Page362.htm
August 16, 2012 12:15:22 AM

OK, I guess I'll just go for 430W anyway. If I really need to upgrade in future I could always get another PSU if necessary, I suppose.
And yeah, I seen that it was 350W on the list, I was just curious about the claim made by the GPU page.
Anyway, thanks, this PSU should do nicely. Shaved a good 20 quid off the price as well. :) 
a c 82 B Homebuilt system
a c 261 ) Power supply
August 16, 2012 12:43:44 AM

The original HD 7750 gets all it's power from the PCI-E slot. The max it could draw is 75 watts. There is a new version that has an external power socket. It can draw 83 watts. ;) 

http://www.anandtech.com/show/5881/amd-announces-a-new-...

Either one is obviously fine with the CX430.
August 16, 2012 2:09:25 PM

Yeah I think the new version is the one I've been looking at.
!