Power supply problems for an HP

I have a problem that I was hoping to get some advice, or more to the point a fix. So on to the details:

I have an older HP xw4000 that currently has a 250W PSU. I recently upgraded to the Nvidia 7600GS 512MB AGP video card. It has one of those molex power connectors to provide the extra "push" required to drive the video card. I hook everything up and install the drivers. Now when I login the Nvidia sentinel tells me the card is not getting enough power. So I stroll down to the local shop and pick up a Dynex 400W ATX PSU. I take it home and plug it in and nothing happens. I then spent a few days researching the issue, after taking it to the shop and them testing it and the PSU works fine. During my research I found that the pinouts on a standard ATX PSU do not match up with HP's motherboard pinouts. OMG! Now what. I have been working on this issue for more than a week with no success. Please help if anyone can!!

Now, what I would like to do is get a PSU 24 pin extender cable for the mobo connector and re-wire it appropriately to get it to work. I have the pinout diags for my mobo and a standard atx power supply but I can't figure out what some of them mean (like Fan CMD and others.) I know you guys are da bomb, I have been looking through the threads and there is some really over my head stuff in some of these posts. I await your expert advice!

Bondalavin

Fan CMD would imply a thermally controlled fan can be used. Older HP's were npotorious for using propritary designs. Without pictures and amaybe data-sheet, it is really hard to see what is going on. Another option would be to pull out the exsisting unit and compare it with the Dynex (a bad buy really, a garbage unit that is made by Shenzen Chi Yuan Industrial Co).

When I get home tonight I will get some pics up and the pinouts I have to see if you can help. I appreciate the input on the PSU as well, but unfortunately thats what I am stuck with at this point. This is for a machine I am trying to make work for the next few months and then I am building a new system. It doesn't have to be great it just needs to work for a while.

Thanks!

I have found the pinouts for the xw4000 as follows:



I am sure you have the standard ATX v2 pinouts, but if you need that I found it at http://pinouts.ru/Power/atx_v2_pinout.shtml

If you still want pics, I can post those tonight. The ones I am unsure about are what on the the standard, goes to what on the mobo since HP calls them different things (Fan OFF, Fan CMD, and Fan Sink.) Some are + and some are - and I am sure they go somewhere specific, but I don't want my limited knowledge cause me to pop the mobo.

Okay, I didn't get home till late, but I did have a chance to check the pins with a voltmeter while the PSU was running. All of the pins were the same except:

Pin -- HP's -------- Dynex
8 ---- Fan OFF --- +5V
11 -- +3.3V ------ +12V
12 -- Fan CMD --- +3.3V
23 -- +3.3V ------ +5V
24 -- Fan Sink ---- GND

On the HP, pin 12 carries .02V and pin 24 carries .4V. I assume these 2 wires are used to control or check that a fan (PSU fan maybe) is functioning?? I also assume if they aren't working properly, that the mobo shuts down the PSU. If I can't provide the right current through 12 and 24, it looks like there is no way to make this PSU work in the box without changing the mobo. I also don't know what the Fan OFF does, but IIRC there is one wire missing from a pin on the HP connector. It might be the fan off. I will be building a new system in a few months, but I wanted to get this one up to speed until then.

Any addidtion advice, or anyone know how to resolve this with the PSU I have?

TIA!

Well, I have decided to return the 400W power supply. I found an internal Power supply that is made by Thermaltake that fits in a 5.25 bay and can run dedicated power to 2 PCIe SLI video cards. The only problem now is getting a connector from the PCIe connector to the 4pin molex. That shouldn't be hard. Doing this leaves the existing PSU and adds a second unit just for my video card. If you want to check it out...

http://www.crazypc.com/products/7259.html

Well, upon further research, the PCIe auxillary power supply only has 2 12V rails and my AGP card needs a 12V and a 5V. Now I am stuck once again.

I did find a more expensive version of this auxillary unit that includes PCIe and SATA connectors. I found that the SATA connector has a 12V and a 5V lead. The only issue now is getting a SATA to molex connector or wire to complete the configuration. Does anybody have any other ideas?