Whats the max watt I can use with my power supply?

nimbah_52

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Oct 9, 2011
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I have a 250 watt power supply in my PC. Here's a picture of it
18dbbq.jpg



Whats the max wattage my graphics card can use with this power supply? Also what is the 12 volt rail etc. ?

Thanks
 
This statement is false. PSU requirements are based on the hardware installed in the system; a lot of low powered systems will do just fine with a 300W or less PSU.
 



Okay well it has

Amd Athlon 64 x2 4800 @2.5 GHz which uses 65 watts
1 sata hard drive
I don't use my dvd drive so I unplugged that to save power

I'm not sure about this but from what I've read 12 volt rail @ 14 amps means I have 168 watts. My CPU takes 65 watts plus lets say 10 watts for my hard drive. So I have 93 watts left. I'm looking at a Radeon 4650 which has a TDP of 55 watts. So all in all it should use about 130 watts.

Am I right?
 


I don't really game much, the first need for speed most wanted and some gta sa is about it. Should be fine for that.
 
The 6450 (DDR3 Version) ONLY uses 8 watts @ idle and 25 Watts at max. Which would be a much better choice given your PSU.
http://www.techpowerup.com/reviews/Sapphire/HD_6450_Passive/25.html

Didn't see manuf, Looks like a Liton (made for HP).
These are generally low-end PSUs. Manuf specs are always suspect on these PSUs as the ratings are at ambient temp and often as the PSU heats up deregulation sets in and you may only get about 60->80% of manuf spec.

For continous operation I would consider max avail power for +12 V rail at 116->135 Watts
Above 116 Watts Usage (12 V Rail) - can any one say Russian Roulette or Crap shoot.
The PSU may last 3 years, then again it may last 10 Min under a heavy load. If it goes you also take a chance that (unlike quality PSUs) it may take part of/all of remaining components.

My Recommendations on PSUs is that if not a tier 1 or 2, do not run above 50% of rated Manuf specs.
 


I can't use any radeon 5xxx series+ plus as my motherboard doesn't support pcie 2.1

Yeah the manufacturer is liteon. I don't want to take the risk with the 4650 in that case. What would you say is the best low power card that will allow me to play stuff like NFS Most Wanted 2005 and GTA San Andreas? Doesn't have to be max graphics.
 
Understand, problem is I'm not a gamer. So someone else can help out there.

What spec is your Pci-e slot. Most newer cards are back-wards compatable. Most 2.1 cards play fine in 2.0 slots, a few DO have problems with a 1.0 slot. Generally you can get a good idea if it will work by reading both prof reviews and user reviews.


Here is a review that shows it running on a pretty old system:
...Quote:
Cons: None so far.
Other Thoughts: My Build:
Refurbished Dell OptiPlex Desktop
AMD Athlon 64 X2 2.6GHz
4GB DDR2 400 (4 x 1GB) Ram
1TB HDD Capacity
Radeon HD 6450
Windows 7 Professional 32-bit
...End quote:
Ref: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102933&SortField=0&SummaryType=0&PageSize=10&SelectedRating=-1&VideoOnlyMark=False&IsFeedbackTab=true#scrollFullInfo

 


It's Pci x16 1.0. There have been one or two reports on google of people having trouble using 5xxx cards on the same pc as mine. I accidentally ordered a 5450 which is coming tomorrow. I'll see if it works but I'm not hopeful.