Hp computer and power supply

[kaniki]

I have an HP Pavilion a1140n here that needs some new caps and a power supply, but i am not 100% sure about how i should connect the power supply. The original power supply was a 20 pin connector with the additional 4 pin by the processor. It does work like that but where i am not sure about is the motherboard. It has a 24pin connector plus an additional 4 pin by the processor. Has anyone run into this before and should I or would it hurt anything to connect the 24 pin connector plus the additional 4 pin connector or just the 24 pin or leave it the way it was.. 20 pin plus the other 4pin connector?

sorry if this sounds like a stupid question.. usually i plug a 24 pin connector into a 24 pin slot and i am thinking that the extra 2 pins on the 24pin slot just give a little more stability and power to everything but do not want to blow anything either. and made me take a second thought about plugging it in when straight from HP, they did not put a 24 pin plug on it, just a 20..

[kaniki]

Re: Hp computer and power supply

also sorry, i think i put this in the wrong listing.. I meant to put it in general computer, not general electronics.. someone called and distracted me and accidentally put it in this one instead.. if it can be moved to the correct listing, go ahead. and thanks

[hardwareguy]

Re: Hp computer and power supply

The 4 pin 12V AUX connector provides 12V to the CPU voltage regulator. The extra 4 pins on ATX-24 provide extra 5V and 3.3V lines.

Fortunately they are keyed so the 4 pin connectors cannot get mixed up. They simply will not fit in the wrong socket.

The usual color codes apply:
Red is 5V, orange is 3.3V and yellow is 12V. Black is common ground. Occasionally you will see an AUX 12V connector with brown and black...brown is for a dedicated 12V supply for the CPU, black is common ground.

On higher end systems, there are multiple 12V lines...usually these are yellow with a colored stripe to denote the individual supplies. (yellow with black, blue and green stripes is whats in my server)

Most 24 pin ATX boards work fine with 20 pin power supplies assuming the old 20 pin power supply is large enough. Most don't have enough current on the 12V rail to power modern machines with powerful graphics cards, but an HP mintower should work fine with a 20 pin power supply.

[kaniki]

Re: Hp computer and power supply

so i should be fine if i put the whole 24 pin plug on and the extra 4 pin plug.. I have never seen a manufacturer do that before. usually, if they have a 24 pin plug, they use a 24 pin plug on the power supply side. I think that these might have been left over and they were just using them up. It was a factopry power supply, but had nothing but molex or IDE plugs for ROM's Hard drives, etc., but yet had a SATA hard drive. so the computer motherboard had a 24 pin plug, power supply had 20 pin. they used an adapter to convert the molex plug to a sata and the power supply was a 250 watt.

what i replaced it with was a 450 watt with a 25A 12v rail, 2A 5v rail. that should hold up.. now, to just get those dang caps soldered in.. having trouble getting 1 to solder into place.. when i went to go take the old one out, the cap went to pieces, as in the lead pulled out with barely any pressure. usually pull very lightly so i can see when the solder is hot enough to slide the cap out, but when i did that, the lead came right out, some of them there internal fluids came out on the one side and am now having a problem getting that side to solder. the old caps were KZG's and am replacing all of them in that size.

[370forlife]

Re: Hp computer and power supply

I would say 99.9% of computers built after 2006ish use a 24 pin main board connector and a 4 (or 8) pin cpu power connector.

If a cpu power connector is there, it has to be connected. 24 pin is optional, as the extra 4 pins provide extra 3.3, 5, and 12v and one ground, it is highly recommended if the board has a 24pin connector.

[kaniki]

Re: Hp computer and power supply

i know that the 20 pin connector was basically mandatory for running the computers motherboard and options, I know that the newer computers use that extra 4 pin adapter for the processor, i just was not 100% sure what the extra 4 pins on the 20/24 pin plug were for. I figured it was for extra power for the extra stuff on the board, but was not 100% sure, and then when HP did not put the 24 pin power supply in it, it kinda made me wonder.. If you are going to use that kind of motherboard, and have the plugs there for the stuff, why not use it? you know what i mean.. and it is not like it would have cost an extra $50 to put the 24 vs the 20 pin power supply in it.. that is what made me double check. I figured it was fine to use the 24 pin plug, just wanted a second opinion.

PS I did use the full 24 pins and got the new caps on and all is right with the world again.. well, it will be once she cleans up her computer a bit.. computer takes forever to start up and shut down.. and running XP with 1 gig ram and 3 gig processor, it should be fairly quick. checked the memory usage with everest and found that the computer was using about 1 gig of virtual memory.. way too much running on that thing..

thanks for all the assurance to what i thought though.. and for all the feedback..

[370forlife]

Re: Hp computer and power supply

Essentially since about ~2000 when the p4 came out they need the extra 4 pin connector. Even some athlon XP boards needed the 4 pin connector.

Well, glad it all turned out ok

btw, what brand 450W is that?

[kaniki]

Re: Hp computer and power supply

true but even the athlon XP processors never started using it until well after the 1 gig range. as for the power supply. it is a "V2 Viotek 450W". The woman that i put it in for did not have a lot of money to spend on one so this is kind of a "charity" fixing.. she will be paying for the parts, but do not expect to get much, if anything, for labor for fixing it. She lives in a nursing home so does not have much for spending money so tried not to spend much on parts. I did get good caps though.. they are Rubycon MCZ's. I did not chang as many as i was planning on though. once i got the board out and after i got the new caps, found out half were 1000uf and half were 1500uf so only ended up changing half of them. but the ones that were bad, i did get changes and the rest do look fine. Truthfully, if i did not change at least the one bad cap, i do not think it would have lasted very long. I have never seen a working cap fall apart the way that one did when i tried to take it out. It was definitely on the very of meltdown. the top was well rounded and the plastic part of the base where the leads are, that was warped and partly blown out too. here is a link to the power supply that i got..

http://3btech.net/newv2vi4520p.html

I went for one that was better then the cheapies, but tried to get something that was still decent and since she a lot of times runs this thing 24/7 and it sits next to her bed, went for the 120mm fan for less noise.. She will be happy just knowing that she is getting her PC fixed, it will come back running and only ran $23 for parts.. All i can say is she better appreciate it..

[Krankshaft]

Re: Hp computer and power supply

The 4 pin connector is two 12 volt lines for the CPU. But that's ancient history now.

I just built my Core 2 Quad 2.5 rig a week ago and it needed a 6 pin 12V connector had to retire my Smart Power 500W for an Earthwatts 650W a very nice Delta unit FYI.

That adds 2 more 12V lines to the CPU.

Not from their own rails necessarily it's just two more wires to balance the current.

The standard changes yet again.

[hardwareguy]

Re: Hp computer and power supply

My new board has an 8 pin 12V connector on it and dual CPU boards have had it for much longer.

There were a couple socket 478 boards without the Aux 12V connector. They were made by PC Chips and no, they were never stable under load with anything more than a 2.0GHz Celeron. I have such a board; it can use DDR or SDR SDRAM but its terribly unstable with DDR. It might be the OST caps but who cares; my friend needs target practice for his shotgun.

I wonder if it will fit in the skeet launcher....