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Old 12-17-2008, 05:51 AM   #21 (permalink)
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Default Re: The right power supply

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Originally Posted by DBD View Post
All I am suggesting is that the rosewill 550 watt will run that rig just fine and just because you drop $100-200 on a PSU doesn't mean it will outlast a $50-80 PSU
true, but a $80-100 PSU from a trusted brand with a good strong single 12V WILL rip **** on a $30 no name piece of junk
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Old 12-17-2008, 05:59 AM   #22 (permalink)
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LOL!! that thing says i need a PSU with over 800W... at only 90% load!! lol!

dont trust junk like that... just buy a sensibly sized PSU from a quality company (eg Corsair, PC P&C, Enermax, etc) and you'll be fine... and always give yourself a little room for OCing!
Just wondering how you know what would be a sensible size for any particular pc, How do you calculate the watts for your builds?

I'm not trying to be a jerk, But the way I see it, Most people spend to much on their psu because they just buy a "big" one...

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true, but a $80-100 PSU from a trusted brand with a good strong single 12V WILL rip **** on a $30 no name piece of junk
$30 no name piece of junk, come on, no one suggested one of those

Sorry bout the bump am ordering the parts in 30 min am I missing anything =)
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Old 12-17-2008, 06:06 AM   #23 (permalink)
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Default Re: The right power supply

no but that was the original one... i dont disagree, the rosewill will cut it, but it soesn't leave much room for OCing or anything (something i like plenty of)

and it doesnt matter how many W its got... you look at the A you're gonna need on each rail and find a suitable PSU... only in rare occasions do you actually look at the W in deciding on a PSU
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Old 12-17-2008, 06:07 AM   #24 (permalink)
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Default Re: The right power supply

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Originally Posted by DBD View Post
Just wondering how you know what would be a sensible size for any particular pc, How do you calculate the watts for your builds?

I'm not trying to be a jerk, But the way I see it, Most people spend to much on their psu because they just buy a "big" one...
Im assuming he was laughing it because the 'ballpark' figure was very high. CF 4850s only sap around 300-350w, and so there is no way the rest of his system saps 500w. If you were to use this calculator for his system, you would then think you need a 800-900w psu which is outrageous.

And on the other hand, 333W for my system seems way to low considering my graphics card saps around 250w under load.
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Old 12-17-2008, 06:20 AM   #25 (permalink)
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Default Re: The right power supply

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Originally Posted by BongWizard View Post
no but that was the original one... i dont disagree, the rosewill will cut it, but it soesn't leave much room for OCing or anything (something i like plenty of)

and it doesnt matter how many W its got... you look at the A you're gonna need on each rail and find a suitable PSU... only in rare occasions do you actually look at the W in deciding on a PSU
Well, how do you calculate how many amps you need on each rail for any particular build?
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Old 12-17-2008, 06:45 AM   #26 (permalink)
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Default Re: The right power supply

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Well, how do you calculate how many amps you need on each rail for any particular build?
Do you mean the 12v rails?

The 5v and 3.3v arent so important, as most power supplies, unless really cheap, will have enough to run everything that runs of them (unless you have 2cpus and 10hdds...). As for the 12v rails, they are what the video card runs off. The amps needed can be found from the video card specs normally.
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Old 12-18-2008, 03:17 AM   #27 (permalink)
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Default Re: The right power supply

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Originally Posted by BongWizard View Post
and it doesnt matter how many W its got... you look at the A you're gonna need on each rail and find a suitable PSU... only in rare occasions do you actually look at the W in deciding on a PSU
brr007

BongWizard is referring to the total watts of any PSU.

Modern PCs have the processor and graphics card draw their power from the 12v and the processor and graphics card uses the most power in a gaming rig. This is why you want a good amount of amps/watts on the 12v rail/s

All the hardware power consumption benchmarks are in watts(that I have seen)

On the 12 volt rail/s of the psu, 1 amp = 12 watts

The 600watt psu you posted in the first post has 24A(amps) on the 12 volt rail(+12V) So you take 24A and multiply it by 12 to get the watts 24x12= 288watts on the 12v rail, Now compare that to the rosewill 550watt psu, and a even better choice(maybe) $60 rosewill 530 watt
Newegg.com - Rosewill RG530-2 530W 80Plus Bronze Certified, ATX12V v2.3/EPS12V v2.91, SLI Ready, Active-PFC Power Supply, UL,FCC,CE,TUV,ROHS - Power Supplies

600watt psu----ATX---------------288watts/24amps on the 12v rail
550watt rosewill ATX12V v2.01-----420watts/35amps on the 12v rails
530watt rosewill ATX12V v2.3------492watts/41amps on the 12v rails

Also there are different versions of ATX PSUs the latest version is ATX12V 2.3, I believe the latest version is the new Intel standard for the core 2 duo (for reasons I wish I knew) and puts more power/watts/amps on the 12v rails where new computers need it most.

The 530 watt rosewill is the new ATX12V 2.3 and it seems like a better choice, BUT it doesn't have 2x 6pin pcie connectors that the 4870 requires, BUT the saphire 4870 comes with 2 pcie adapters and the cooler is better(I think) Newegg.com - SAPPHIRE 100259L Radeon HD 4870 512MB 256-bit GDDR5 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card - Desktop Graphics / Video Cards

Dose anyone know if there is a down side to using the pcie adapter?
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Old 12-18-2008, 07:27 AM   #28 (permalink)
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Default Re: The right power supply

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Originally Posted by BongWizard View Post
no but that was the original one... i dont disagree, the rosewill will cut it, but it soesn't leave much room for OCing or anything (something i like plenty of)

and it doesnt matter how many W its got... you look at the A you're gonna need on each rail and find a suitable PSU... only in rare occasions do you actually look at the W in deciding on a PSU
the rosewill will be fine, rosewill is not a bad brand. its got 36 amps over the 12v rails which will be fine for your system, even with overclocking.

now as for your build, i would get this WD hdd
Newegg.com - Western Digital Caviar SE16 WD3200AAKS 320GB 7200 RPM 16MB Cache SATA 3.0Gb/s Hard Drive - Internal Hard Drives
about the same price, more storage. there is also seagate counterpart for same price if you insist seagate.

this ram is better timings and cheaper, good ram
Newegg.com - G.SKILL PI Black 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) Dual Channel Kit Desktop Memory - Desktop Memory
now you could upgrade cpu to a e8400 which is alot better, but if your tight on cash then the e7300 will do fine. For that system what i would do is downgrade to a 4850 and get a e8400. unless your gonna be playing at a bigger res then 1680x1050 a 4850 will be fine.
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Old 12-18-2008, 06:51 PM   #29 (permalink)
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Default Re: The right power supply

Ok, hypothetically, could that same 550W rosewill handle a GTX 280 Newegg.com - Suggested Products

EDIT: better question -- does the amperage distribution across different 12V rails matter? (will the power supply automatically correct and give a GTX 280 a full 40 amps down two 12V rails (if thats all I can manage to connect to it) if it has 18A max on each of 4 12V rails?

Newegg.com - OCZ GameXStream OCZ600GXSSLI 600W ATX12V SLI Certified CrossFire Ready Active PFC Power Supply - Power Supplies
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Old 12-18-2008, 08:45 PM   #30 (permalink)
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Default Re: The right power supply

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could that same 550W rosewill handle a GTX 280 Newegg.com - Suggested Products
No, the 550 watt rosewill only has 35 amps on the 12v rails.

Quote:
Originally Posted by brr077 View Post
EDIT: better question -- does the amperage distribution across different 12V rails matter? (will the power supply automatically correct and give a GTX 280 a full 40 amps down two 12V rails (if thats all I can manage to connect to it) if it has 18A max on each of 4 12V rails?
I belive they are recommending a 550watt psu with 40amps(480watts) available on the 12v rails for your whole system, not 40amps for the GTX 280 alone.

4x 18amp 12v rails, doesn't mean you have 72 amps on the 12v rails. it means you have the ability to use 18 amps on 1 rail max BUT the remaining 3 rails wont have all 18amps available because it doesn't have 72 amps to give.

It appears that the ocz you linked to has 580watts to share with the 3.3v, 5v and 12v but the 3.3v and 5v can use up to 155 watts of that 580watts.

lets say the 3.3v and 5v use all the 155watts available, then there would only be 425watts available on the 12v rails or 35.4amps to share between the 4x 12v rails.

http://c1.neweggimages.com/NeweggIma...341-001-05.jpg

Also, hardware draws the amps/watts that it needs as long as it's available. a 600 watt psu doesn't use 600 watts surfing the web.

kinda complicated huh? lol
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