Power supply for new graphics card

_____A-L-E-X_____

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I am purchasing a new XFX 7950GT AGP (512mb) graphics card and I was wondering if I have to upgrade my PSU or if its good enough-- I have an Antec Smartpower 2.0 SP-450 (450W) that is almost 2 years old. The other peripherals I have hooked up to it are two hard drives (40GB and 120GB, both Seagate Barracudas), a Vantec Tornado 80mm case fan (0.75A, 9.1W) a dvd burner, a cd burner and a floppy. Case has 6 usb ports, all in use (one with a hub) and I have a 2.8GHz Pentium 4 with 2GB of PC2700 memory. I also have an Audigy 2 ZS sound card... and thats about it. Thanks in advance!
 

Ananan

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I had a smartpower 2.0 500W and it choked when I added a 7800 GT to my PC. It could run with one CD drive but wouldn't boot when I plugged in the second; that bit of extra power apparently sent it over the edge.

I'm sure it was a bad unit not indicative of the general quality of that line. Still.....

I feel much safer since I installed my NeoHE 550 W.
 

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Thats what Im wondering about. This psu has dual 12V rails with 15V on one rail and 17V on the other one. With the 2 hard drives, Im hoping I dont overload the PSU also.
 
I think it will be ok checked some info and the specs say different things depending on board partner some say 350watt psu some say 450 watt psu have also checked some reviews which say it runs about 60-65 watts at full chatt in 3D which is about 5.5 amps.
Mactronix
 

honestjohn_

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Well, that was my last AGP card which I sold about a month ago. The recommended power requirements for the card as stated on the box are 450w and 20a on the +12v rail or combined rails. Read the specs of your PSU over on the Antec site and it looks like your power supply should just handle it. This assumes that your +12v rail hasn't degraded too much over the past two years. Worst case you'll need a new PSU which should run you about $110 on NewEgg. If it comes to that, I'd recommend either the Enermax Liberty 500w with 32a of sustained/continuous power on the combined +12v rails for $109. Excellent Reviews and Prof. and user. Or the Corsair which is even beefier with a 40a on the combined +12v rails for $129. Good luck with the card, it's a good one.
 

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Thanks... that looks like a great deal. I just might pick it up regardless of whether or not the sp-450 works... Im kind of nervous about the 15A/17A rail combo underpowering the 7950GT
 

kpo6969

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Personal preference I suppose. Depends if you rather have 1 rail or 3. The 550 has 9 more amps but if you have less power-demanding requirements I'd rather have 33a on a single rail as opposed to 42a split 3ways. Both are same price and very good.
 

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Ugh, I found out I might not be able to use the corsair because I have a microATX which is just barely more than a foot long (about 15 inches or 400mm) while all the cords (about 17 in all) are over 600mm long in that power supply. And my video card is 8 inches long so there wont be any room to put those cords anywhere.

 

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Awaiting graphics card delivery On friday. Meanwhile, I thougt I'd test the psu I have now so I downloaded everest, motherboard monitor and sisoft sandra and checking for voltages- MBM reports +3.3V at 3.29 and +5V at 5.02-5.05, my -12V is -11.67V-- but get this: the +12V voltage and the -5V voltage are 0.00 ! I get similar readings with everest and sisoft except they dont even show the +12V and the -5V readings! I havent had any PSU problems and I use an overclocked 6600GT... does this mean my PSU is starting to go bad, or that maybe the sensors are malfunctioning? I havent used any of these programs before so I really dont know if its my PSU or the sensors.

edit: I should also add that Ive left my computer on for days at a time (more than a week at times) without having to restart or getting kicked offline or anything. The only thing that I get is some sort of memory could not be read error at startup and when I click desktop icons... but after I click OK and the taskbar reloads, I dont have any further problems with that. I think thats my 3 yr old RAM anyway, which Im about to replace.
 

sdrac

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In the 4.10.1119 beta build of Everest, if you turn on logging you'll be able to see your +12V (and lots of other things) while your gaming, etc..
However, if you want a real accurate reading, buy a cheap multimeter and hook it up to your molex connector, for instance, to test +12V and +5V. Leave it there while your system idles and then while gaming - you'll get a good idea for how well your PSU is holding up.

sdrac