fan on psu stopped working

Hello,
I finally get the pc up and running and everything working perfectly and now the fan on the psu stopped working.

I spray some canned air into the psu fan and used a q-tip and it moves freely but when plugged it it does not work. I have also tried the paper clip test and I can hear the hard drive run but no fan. I am guessing that I need to replace the psu unit in this thing before it overheats and ruins the motherboard or fries something else. (can't see how to get the fan working in the psu). The other fans inside the tower are working just fine.



The current psu states model NPS-250GB 8
INPUT 100 - 200V ~ 9.0A 50 - 60 mz
200 - 240V ~ 4.5A

Output 250 max

MAX COMBINED POWER ON +5v and +3.3V output is 170W
Date Code 0204

I cannot find any information on a manufacturer of this power supply

The dimensions are 5.5" front to back
6" side to side (where it faces back of pc tower)
3 3/8 " deep.

I did find a link with a couple of suggested units http://www.coolscreens.com/upgrade_dell.html

and this site suggests the Thermaltake W0070RUC TR2 Series 430W Power Supply
which I did find at http://www.newegg.com/Product/Product.aspx?Item=N82E16817153023

There was also a suggested psu Startech.com 400 Watt ATX12V 2.01 Dell PC Replacement Power Supply

and StarTech.com 300 Watt ATX Replacement Computer PC Power Supply - ATXPOWER300

StarTech.com 350 Watt ATX 12V 2.01 Dell Replacement Computer PC Power Supply ATX PW350DELL

I also found the same size psu through a dell link which is recommending the ATX12V-250DL (BESTEC ATX-250-12ZS)

and another link suggesting another 205Watt power supply (free upgrade to 300 Watt) at http://www.cputopia.com/replace-250w-dell-dimension-4400.html

Any Suggestions would be so Very Much appreciated.

Thanks!

 

Umm, isn't your heatsink fan connected to the motherboard? That's usually the case. Other fans can connect directly to the PSU as they don't have the 4th pin to control speed. Ya, your power supplies leave one wanting a bit more.

 

Seconded. PSU is probably fine. It is more likely a dead fan. Depending on the CPU cooler you can probably replace just the fan for a few £

 

The fan on / in the psu isn't working. The other fan is working just fine. From what I can see there are only 2 fans in total on this unit. The one inside the psu and the other one that is working. If you look at the Dell Documentation @ http://support.dell.com/support/edocs/systems/dim4400/replace.htm There when you look at the information about replacing the microprocesser it shows the heat sink and the fan and shroud that directs the air to the heat sink. And that fan does plug into the motherboard and is working.

The PSU is working but the fan is not and it is getting hot and the last time it was on it started to smell hot so I shut if off. I did take the psu out of the hp to test the dell and to in fact make sure that the other fan is working and all is fine there.

The HP machine does have a fan that is in fact directly on top of the heat sink and plugs into the motherboard as well as a fan with a shroud that is directly over the heatsink and fan as well as the fan that is in the psu. So I do understand what you are saying about the fan and heatsink but that is not the way this dell is set up.

 

The fix is obvious now, don't go and open that PSU sucker to change a fan as you could get really shocked!

Small PSU's like that are inexpensive.

I should have read the title to this thread.:-o

 

Im going to blame augiedoggie for missleading me as I most definately didnt missread your post an think you ment CPU!:-o

 

One other thing. I did find some information from the dell link and their suggestion for a replacement and that was for a Bestec model ATX-250-12Z. But if I am going to replace the psu I would rather go with something with more power then 250Watts

 

That's fine, I've got a thick skin.

You have to make sure that the pinout for the replacement is the same as the Bestec. Other than that, you're good to go.

 

I'm guessing that I am correct in thinking that I need to replace that psu if the fan is not working since it is only going to make it pretty hot and eventually it will cause the psu to fail (only guessing here).

My thoughts are that going with a larger psu (if in fact I should replace it) would be a good idea as well. As to size / power not sure about that one. But it does have a 250 watt in there now and I have also been doing some more searching and found another 400 watt replacement for the Dell at http://www.cputopia.com/replace-250w-dell-dimension-4400-1.html.

I did check and the Thermaltake is a little bit larger in size but there is enough room in there for it to fit. The Thermaltake is 6.3" x 5.9" x 3.3" and since according to the Dell suggested replacement is Bestec ATX-250-12Z which measures 5.5" x 5.9" x 3.4" there is a slight size difference but I do have about another 3/8" - 1/2" in space (above / over the 6") and still be able to close the tower.

The only reason I even found the Thermaltake was when doing the search for replaement psu for the Dell dimension 4400 it was a suggested unit at http://www.coolscreens.com/upgrade_dell.html.

But if anyone has a better suggestion I would greatly appreciate it.

 

I hate to sound stupid augiedoggie but what do you mean by pinout?

 

No worries man, pinout is where all the power comes into the mobo. Some companies liked to make their own pinout(change how power comes in 20/24 pin input) so that one would buy their stuff, if your machine is post 2K4 or so then I see no issues.

http://www.google.ca/search?q=power...PEsvD0AHG8aXGBQ&ved=0CDwQsAQ&biw=1920&bih=979

 

Thanks for that info. Well the pc was given to me and the motherboard pin is 20 but I had to replace the psu in an HP Pavilion in the past and that was a 20 pin as well but the new psu came with the 20+4 pin for the motherboard. The extra 4 pins on the end just aren't plugged into anything. I had gotten that one at directron.com (when I posted this I couldn't recall where I had gotten that one - but found the reciept). In fact it was the psu from the dell that I used to make sure that everything else was running fine on this dell. The Dell machine has a manufacture date of 3/3/02 on the bottom of it.

I did come across a replacement for the Dell at directron as well and then found the same thing on ebay from KDM for $37.49 vs. Directron which is charging $56.27 (both appear to be the exact same thing and have the exact same model number to them) and it is a 480watt psu.

I had been thinking about that thermaltake psu since it also has 2 fans on it and right now on newegg.com there is a $12 rebate and another $4 off at checkout giving it a final cost of about $25 but the difference in size had me concerned and then when I did some more research I found that the unit also has an on/off power rocker switch and I would have to alter the case for that switch to fit. (not going to go through all that).

So it would seem that it is a good bet to replace that psu and it looks like I may have made my choice of which one to get as well (and the kdm one also has a little more wattage to it too)

Thanks!

Lisa

 

its not just the number of pins but the mapping of them. Your computer uses many different voltages. A bought PSU will use standard ATX pinout (mapping) but your motherbord may have a custom pinout. so if you plug a standard ATX PSU onto a motherboard with a custom pinout then you could connect a 12v supply that should be getting 5v. This is obviously not good. Dell are pretty good and probably publish thier pinout on the webside or in their service manuals

 

Okay - now I'm a little worried about just what psu to get.

I did read on a dell forum that "The Dimension 4400 uses a standard generic ATX power supply with either a 20-pin or 20+4-pin main motherboard power connector, without the on/off switch, if you use a PSU with the switch, then you will have to modify [cut a hole] the back panel of the case for it." http://en.community.dell.com/support-forums/desktop/f/3514/t/19338103.aspx Further down in that same post "most standard ATX power supplies will be fine, as the Dimension 4400 does not use a Dell proprietary unit, but if the power supply has the on/off switch, you will need to cut a hole in the back panel for it."

The part about cutting the hole to fit an on/off switch is why I decided against the Thermaltake (and the fact that it is a teeny bit larger ~ but I have the room for that small an amount of difference). The Thermaltake is supposed to be a standard ATX power supply but not going to take the chance that I am wrong about it fitting and don't want to bother with having to cut a hole to fit that on/off switch.

After what you said I did start looking for information on the Dell ATX power supply pinout and did come across a couple of sites with information and a diagram about the pinout but to be honest, I'm not sure what to be looking for. http://pinouts.ru/Power/dell_atxpower_pinout.shtml
http://www.informit.com/articles/article.aspx?p=339053

There was one site with information about Dell to ATX power supply adapters and it states "Your Dell Power Supply May Be Proprietary - A standard ATX power supply will even physically fit into the Dell computer and the electrical components will look like they line up, however, if you don't use a proprietary Dell power supply or a Dell to ATX Power Supply Converter with your standard ATX power supply, your computer will not work and damage may occur to the motherboard and/or the standard power supply." But..... the Dell site/forum states that the Dimension 4400 uses a standard generic ATX power supply. And further down on that site it also states "Known exceptions:

Pentium 4 Dell Models that do not require a power supply adapter:
Dell Dimension 4300, 4400, 4500, 4700, 8200, 8300, OptiPlex GX 400"

There is also a picture of a motherboard & connector of a Dell that would require the power supply adapter and neither the motherboard or connector on this Dell look like that.

Soooo.... now I am really confused. I did look at the pics of the non standard ATX wiring and I am not sure exactly where you would start (which one is pin 1 sort of thing). However, the picture does show that the grey wire is located in pin 11 on both of those sites and the grey wire on the psu that is in there now is not on a end but is located further in on the connector. Also the yellow wire on those diagrams is not on an end of the connector and on the one that I have it is. So does that mean that the psu is a standard ATX and I can go with the KDM?

 

Was just looking at the KDM power supply unit again at directron and it does state that it is compatible with the dell dimension 4400 and I did email them to ask as well and they did confirm that it is compatible with the pc. But I am a little concerned about that pinout thing (as stated in my previous post).

I do have one other question - this one regarding the different KDM power supplies. The one at directron states "KDM Nickel Coating 480W ATX v2.2 Switching Power Supply M6480H2.2, 20+4 pin, Supports PCI-e, SATA, AUX, w/ HP Video Power Connector and Dell P6". And the one that I found on ebay (seller is KDM Power) does not state Nickel Coating but the model number is M6480H (missing the 2.2) but I also contacted them and they also stated that it is compatible with the dell dimension 4400. I could see a picture of the motherboard connector at the ebay site for kdm and it looks just like the one I have now. The one on ebay does not state Nickel coating (guessing that is what the 2.2 at the end of the model number is) so what is the nickle coating? I did go directly to the KDM site and if you are interested in the nickle coated version it directs you to directron.

Also noticed that the one that is nickle coated also states pci express 6 pin ready - not sure what that is either. Can't located a picture of all the connectors at the directron site.

 

I located the Dimension 4400 service manual here which I can confirm following a comparrison with the ATX pinout here that a standard ATX psu will be fine. pin 18 is different but that is optional and not connected in your case. Therefore any ATX PSU without a powerswitch will be fine.

The 6-pin PCIe connector is to power PCIe gpus. however according to the documentation your system uses AGP so the PCIe is not relevant.

 

Thanks so very much for all the help and clearing those things up for me. Now I feel comfortable with making my purchase.

Again, Thank You Sooooo Very Much!

 

Your welcome. Let us know how it goes!

 

Just an update, I did get the kdm power supply unit and installed it upon arrival yesterday. All is working fine now. This power supply unit is much smaller in size than the original one that was in there so it fit just fine and the screw holes did line up. This power supply unit has over 400Watts of power vs. the original 250Watts.

When this unit had been given to me I originally noticed that there would be a brief sort of spinning noise when the pc would start up so when the hard drive died just a few days later I figured it was that. Then after getting everything squared away with that and getting it up and running again I noticed that noise started again so when the fan in the power supply died I figured it was that but when I turned on the pc today that very brief sound is still there (does sort of sound like a fan spin type of noise) so just to be on the safe side I'm thinking that I might want to look into getting a fan for the heat sink - just in case that fan goes too. But before I do that I am trying to figure out what other possibilities there are for that noise. All the lights on the back of the tower are green so going to the Dell site to see about those for diagnostics won't help.

Already put a new hard drive and power supply into this thing and it was free so if I can figure out what that noise is and as long as it isn't anything major I will look into getting that fixed. Then I might give this unit to my parents.

 

Have the side open, use an empty paper towel tube like a stethoscope and listen to the various fans starting up when booting, especially when cold like the next morning, beginning with the heatsink fan as that's obviously the most important.

 

I'll try that tomorrow when I turn on the pc. There are only 2 fans in this dell dimension 4400. The one in the power supply unit and the one for the heatsink. At least that is all that I have ever found in this thing and according to the documentation there are only 2 fans as well. (http://support.dell.com/support/edocs/systems/dim4400/replace.htm)

Will let you know what I learn tomorrow after I turn the machine back on.

Thanks

 

Well, I did as you suggested and I did hear that sound but now I'm not sure that it is actually coming from the other fan inside the tower. The hard drive that is in the unit is brand new as well as the power supply unit. I have been learning about the insides of the computer as I go along so I'm not sure what else there is that could be spinning on startup.

Maybe I am explaining the sound incorrectly but to me it sounds like a brief spinning noise which only lasts for probably about 2 - 3 seconds and then I do not hear it again until the next time the pc is turned on. I have taken the fan that cools the heat sink out and cleaned the blades and used compressed air on it.

Any suggestions as to what that noise may be or what else to check?

 

There's still might be a chipset fan on the mobo, small thing maybe 1" sq, it could also be just regular start up noise like your CD drive being accessed or just a loud hard drive. Anyone's guess is good at this point.

 

I will look again to make sure that I didn't miss any fans in there - who knows if it is that small maybe I did!

Since the noise was there before the original hard drive died and is still there since it was replaced (original was an IDE Maxtor - I think a 40gb which was replaced with a WD 160GB) I'm guessing that maybe I missed a fan that small or like you said perhaps it is just the CD Drive being accessed on startup. I could always disconnect the CD drive and then start up the pc and see if the sound is still there. If it is then I know to look for a really tiny little fan somewhere on the motherboard and if it isn't at least I know what is causing the brief noise on startup.

Thanks for the suggestions!

Lisa

 

Well, just out of curiosity I unplugged the cd drive and started the pc this morning and that noise was gone when I turned it on so apparently that sound is in fact the CD drive being accessed on startup. At least I now know what that noise is and it isn't anything to worry about.

Thanks so Very Much for Everything!

Lisa :celebrate

 

I bought the KDM one too. I took the power supply Fry's to install and they have the same one made by Athena Power. It's the same exact power supply with nickel coating. I just payed almost double the price for nothing. The Fry's associate told me Athena Power makes the power supply for KDM. What a scam.

 

The first power supply unit that I purchased I got from directron.com and that one stated that it was nickle coated. The one I purchased for the Dell I bought on ebay.com (brand new and from kdm - seller kdmpower) but this one was only half the price and does not state that it is nickle coated but they both look identical to me (other than the sizes of course) You just never know who is making what anymore.

Lisa