View Full Version : Power Supply Question (FX 5950 Ultra)

Nick W
05-18-04, 04:01 AM
Hi all,

I have a 300W power unit and my FX 5950 Ultra is saying that it is not connected? - It is!

I understand that it requires a 250W PSU but I am running 2 hard disks off of that PSU right now, could this be the problem?

If not, can anyone offer any advice about getting it to work properly?

(it of course does work, but keeps complaining.....)

Many thx


05-18-04, 07:05 AM
The problem could be the quality of the power supply. A power supply could say it is 500Watts, but is it really?

This months issue of MaxPC explains power supply issues. I always say good with a good power supply from a major company like Antec, Enermax or PC Power and Cooling.

Just my 2 cents.

05-18-04, 07:41 AM
What Scott says is true. You can have a quality 350W psu that actually supplies more power than a generic 400W psu. I have an older model quality built 340W psu that actually peaks at around 380W. Evaluating ATX switching power supplies can be confusing, to say the least.

Something to do for fun and at the same time get some indication of your power supply needs is try a little program like this one: http://www.jscustompcs.com/power_supply/

05-18-04, 10:52 AM
i've always been totally anal about power supplies, heh. i've got an antec 400W psu right now, which cost me $50, and i'm still a bit concearned about it, heh. i guess the main reason why is not so much power output, but quality of output and the chance that the psu will go bad and ruin everything in the computer. i guess horror stories will do that to you.

btw, afaik didn't the 5950 require a 350 watt psu? -- i was pretty sure it was 300, or 350 -- but maybe i'm just crazy. at any rate, i'd never get a PSU under 350watts; so even if that isn't the problem, i would suggest upgrading the power supply.

i guess that's just me, heh. probably not everyone is quite so worried about PSU's as me.

Nick W
05-18-04, 11:06 AM
New PSU ordered ;)

420W - prolly a 'cheiftec', as it seems im a litte limited out here in the darker parts of lolland, Denmark ;-)

Thanks for all the advice, i'll let you know how it goes when I get it on Friday..!



05-18-04, 02:32 PM
Ya I was just gonna say 300w aint gonna cut it. I actually had an Enermax 350w and even it had trouble handling my FX5900Xt. I was really surprised because Enermax is suppose to be high quality, but I switched to an Antec 550w and the Nvidia power warning box finally went away.


05-18-04, 02:36 PM
ya please post results, i have been having major problems, with my 5950 saying it is getting no power to it, i have a 420W Raidmax, good luck on the psu

05-18-04, 03:28 PM
New PSU ordered ;)

420W - prolly a 'cheiftec', as it seems im a litte limited out here in the darker parts of lolland, Denmark ;-)

Thanks for all the advice, i'll let you know how it goes when I get it on Friday..!



Chieftec power supplies are subcontracted thru various makers. If you get a 400W+ power supply (or any psu, no matter what the wattage rating) I would strongly suggest that you make sure it has at least an 18A rating on the +12V rail. I have mentioned this a number of times but IMO with the new CPUs and video cards being supplied by the +12V rail that you need all the Amps you can get on this rail. Some of the new quality power supplies are offering as high as 35A rating for the +12V rail. That ought to tell you something.

05-18-04, 05:54 PM
My advice?

Bite the bullet and get the highest quality PSU you can get, then you are F'n done and can expand as you please.

I have an Enermax 550 and love it to death. I prefer Enermax, Fortron(for value), Antec, and Thermaltake. There are others out there that are good, but these are the quality ones IMO. I shouldn't neglect to mention Zalman, darn fine PSU's. Thing is I think they top at around 400.

If you have time read this review/comparison:




05-18-04, 08:45 PM
I love my Enermax Noisetaker... Antec Truepower, and PC Power and cooling PSU's are about the best you can get

Nick W
05-19-04, 01:54 AM
What do you guys think of this?
Lepont Red Vigor (http://www.studiedata.dk/productitem.asp?id=PSLP122&Fane=CASE,CAPS)

It is 520W with a 20A rating on the 12V rail.

How would I know/find out if it will fit in my cabinet? - it's 2.5Kilo! hehe...
Im a bit worried about that, what's the best course of action?



05-19-04, 07:31 AM
Don't know anything about the psu but it says it meets ATX case specs so it should fit without any problem.

Nick W
05-19-04, 08:34 AM

You think there is any risk to my fx5950 running it with insufficient power for a fiew days?


05-19-04, 08:55 AM
Long as you're not gaming you should be fine. The card will run at a much lower clock speed until you get that PSU in hand.

Nick W
05-19-04, 09:07 AM
Ok, cool. Have not been gaming for that very reason :-)



05-19-04, 10:53 AM
that psu is excellent. never heard of the company, but by the ratings i really don't see where they could cut corners. the weight is a very good thing btw, the more a PSU weighs generally the better the PSU; because it will generally have more transisters and capaciters for cleaner, less varying voltages.

your card will run excellent on that PSU (along with 4 hard drives, lol). don't know how much that is in american currency, but i wouldn't mind having one myself :D lol.

05-19-04, 11:09 AM
I used to have a variant of one of these power supplies (http://www.tigerdirect.com/applications/searchtools/item-Details.asp?EdpNo=561177&sku=P456-1004). It didn't have the colored case, but it had 500W, 25A on the +12v and cost $70. That power supply ended up in a friend's PC, whose case was partially destroyed in a fire. After opening up the PSU and giving it a good cleaning, it returned to normal function. I think that's a pretty strong testament to the quality/value of Powmax units. I wouldn't hesitate to buy another one.

05-19-04, 11:34 AM
this (http://www.newegg.com/app/viewProductDesc.asp?description=17-103-912&depa=0) is my current power supply. if anyone is looking at getting an antec, i would suggest getting the one i have (the "smart" power) as opposed to the true power. the true power is a better PSU, but at half this price, this PSU is very nice.

i personally have no problems with it; am running 3 hard drives and an optical drive, along with an o/c athlon xp2500, and 4 case fans (2 variable speed... but i made them go at full speed :D).

the only thing i don't like about mine is that i feel the fan is too low of an rpm, or atleast the heat is pumping out of the back of it quite a bit. if i were guessing the temps of the air coming out of the back of the PSU is about 120F -- whereas my case is only about 100-105. i suppose this doesn't add to the case temp, but really noise comes second to cooling for me. i've got 3 computers running in my room, so the added noise of a higher rpm fan is not noticable.