My new power supply won't cut it huh? :( HELP!

dbrimberg

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I have been buying the pieces for my new gaming machine for a few months now and after seeing the power consumption of the 4850/4870 in Crossfire in other posts I don't think the PSU I bought (Corsair CMPSU-520HX) will cut it with my new system. Perhaps someone could direct me to a PSU that isn't overkill but will be perfect for my soon to be completed system. I bought a E8400 but at the last minute switched to the QX6850 due to an amazing deal. Thanks for reading this post and helping me out.

My setup:

Power Supply: Corsair 520HX
Processor: Quad Core Extreme QX6850 Kentsfield 3.0GHz
Motherboard: Gigabyte GA-X48-DS4
Memory: (4GB) Mushkin DDR2 800
HDD: (2) Western Digital 250GB SATA 3.0Gb/s
DVD: Samsung DVD Burner
Heatsink: Zalman 9500 AT
Video Cards: HD 4850 crossfire or 4870 in Crossfire.
 

dbrimberg

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I haven't used the PSU yet, it's NIB still. So I will either sell it or see if newegg will take it back. Either way, I probably need a different one and would like for you, or others to chim in regarding which range of PSU's I need to be looking at for my set up. Thanks!
 

cliffro

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I like the 750TX as well, its got enough balls, [H] called it a "Good" PSU not great but definitely good. And it isnt excessively priced compared to other 750w PSU's from other Major companies.

Actually if I could afford it right now, I would have one myself. But alas my finances are crap so i have to wait.
 

psymanproductions

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the 520hx WILL work, dont believe me, try it!

even if i am wrong and the psu cant handle you system the worst that could happen is that the psu will turn its self off.

crosshair are a good make and their psus will automaticaly power off in the case of exessive power draw so you have nothing to loose, people allways over estimate the power consumption of high end pcs and it makes me laugh to see people recommending 750w psus for your rig. if you didnt already have a the psu i would recomend something around 600w so you have some room for overclocking and upgrades but 520 will be enough.

here is a source to back up what i am saying... dont waste your money

http://www.behardware.com/articles/670-4/pc-s-actual-power-consumption.html

ive read about 10 articles basicaly showing the same thing but i cant be arsed to find em all for you... dont believe the marketing hype
 

The_Blood_Raven

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How do you think I feel with my brand new PC P&C 750w? Guessing from the 4870 power requirements my future 4870 X2s in CrossfireX are not looking so hot... oh well I suppose I will have to only buy 2 4870s and actually get good performance for my money.... Anyway the PC P&C 750w is the absolute best, or damn near it, 750w PSU on the market and is at a good price, for the red one.
 

The_Blood_Raven

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The system with 2 8800 GTXs needed almost 700w at load.... maybe you missed the boat and did not see that his CPU is more demanding than theirs and the cards he wants use more power.... guess 750w really is what you need judging from this. Oh and do not forget, or considering this post please try to actually understand, that a PSU runs best between 25%-75% of the rated wattage, and that's even pushing it. Unless that system would push less than 450w, then even that 520HX would have a relatively short life span.
 

houstonserenity

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dbrimberg

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Alright, is there a better power supply in the price range compared to the 750TX? PC P&C or anything else. My limit has to be $140 or so... heh
 

psymanproductions

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a 8800gtx consumes more power than a hd4870,

a 65nm cpu at 1.5v is VERY unrealistic and will add a **** load of power consumption, even over the 3.2ghz quad he has it will consume ~ 50w more than his i would say

the systems memory was over volted to 2.25v adding ~20w i would estimate

the system in the test set up had 4 hard drives adding at 10w at the very least,


GeForce 8800 GTX had an 185W maximum TDP at launch, dropping to 177w a few months later. acording to http://www.bit-tech.net/hardware/2007/05/02/nvidia_geforce_8800_ultra/1

hd 4870 has a tdp of 155w, (a rough averarage of sources only found in forums etc as there was no official source anywere)

the power source in the article http://www.behardware.com/articles/670-4/pc-s-actual-power-consumption.html actually SUPPLIES 567.6 watts under these exreme conditions, it CONSUMES 687.6 watts at the wall - PSUs are rated for what they SUPPLY, not what they CONSUME,

so to conclude he WILL be able to run his set up on a 520w psu from a good manufacturer

you say a psu runs "best" between 25 and 75% of its maximum rated output... if you mean it has most of its efficiency in this range then you would be correct, the fact that his pc will stay idle most of the time, unless he ONLY uses it for gaming means it will be in this high efficiency band most of the time, unlike most people who buy over powered psus.

why will running a psu near it limit shorten its lifespan? i have seen no evidence for this, please show me some.