Resolved [Power supply for Dell Dimension XPS T 700r]

I have had the above referenced computer since June, 2000. It has a pentium III processor and basically stock with the only addition being to max the memory and change the O/S from Win 98 to XP Pro. It also has a 30G HD, DVD r/w and CD r/w. It has served me well until now. It died. I pulled the power supply and confirmed it was indeed, dead. After much searching, I found another P/S with the appropriate plugs for my M/B. I installed the new P/S and - nothing. Power is good from the outlet through the plug. The fan doesn't even start. I tried another new P/S bought from Best Buy and it too failed to function. How do you check a P/S, w/o a multimeter to see if working? Thanks, Dennis

 

Welcome to the boards. Google Power Supply Tester. They run any where from $10.00 and up.

 

By swapping in a "known good" one or as MrBill suggested, use a tester. While testers are not 100% conclusive, they are pretty good. But they do not test for excessive ripple and other anomalies that affect computer stability. I keep this PSU Tester in my tool bag in my truck. The advantage of this model is that it has an LCD readout of the voltage. With an actual voltage readout, you have a better chance of detecting a "failing" PSU, or one barely within the required tolerances.

 

Thanks for the replies. I'll get a tester.

 

Something else to consider is way back, Dell was notorious for using non-standard PSUs and motherboard power connector configurations. The 20-pin main connector was not wired in compliance with the ATX Form Factor standard (a couple of the wires went to different pins). This use of proprietary parts was (IMO) to force users to buy more expensive replacement and upgraded parts only from Dell. Not cool!

Because both the PSU and the motherboard 20-pin connectors were not wired according to the ATX Form Factor standard, connecting a compliant ATX supply to one of those proprietary motherboards would not work - and in some cases, caused further damage.

Your 2000 system may be one of those systems. You need to verify your system uses a standard ATX supply and not one of Dell's proprietary designs. See here for more information. Do not pour good money after bad. It may time to upgrade to a modern system.

 

I did not know this. The person from whom I obtained the new power supply, on ebay, said it was the correct PSU for my Dell ATX and the plugs are the same.

 

That's the problem and what caused so many frustrations. The 20-pin plugs are exactly the same on both the PSU and the motherboard. But the pin-outs (which wire goes where) is different. There are adapters but you must ensure the Dell is proprietary before using an adapter.

I never trust what I read on ebay.

 

I installed the PSU after checking to make sure it works. Without attaching any plugs, I jumpered the main grn/blk wire on the 20 pin plug and the fan started. After connecting all the plugs into their respective recepticles, I pushed the start button. Nothing. Fan doesn't turn. No lights go on. Evidently no power. No smell of anything frying and no sounds.

 

If the PSU is working and the correct model, then it would appear the motherboard is toast. Considering it is 13 years old, I'd say it had a good run.

BTW - sadly there is no industry standard requiring specific wire color coding for PSUs. For today's PSU's there is a recommended color coding that most makers comply with, but it is not mandatory. So you really should go by pin number, not wire colors.

The only other thing I can suggest is to disconnect/remove everything from the motherboard except 1 stick of RAM, the CPU and cpu fan, and the main 20-pin power connector, keyboard, mouse and monitor. No drives, no extra USB devices, no extra add-in cards and then try to boot. If the motherboard is good, you should see on your monitor the POST (power-on self test) and the initial stages of the boot process, then failure as no boot drive is found.

I assume you hear no beeps, right?

 

That is correct, no beep - nothing. I will try your suggestion. Thanks

 

No beeps could indicate a serious problem (like dead motherboard) or it could just mean no internal speaker. Back then most motherboards did not have an integrated speaker and instead, relied on a case speaker. And back then most cases had one.

But today, most motherboards (but not all) have a tiny piezoelectric speaker mounted on the board so most new cases do not include a speaker. But sadly, since some entry-level boards don't have an integrated speaker (the extra $.10 will bust the budget! ) the user is left with no beep tones. Fortunately, all motherboards still provide support for an internal speaker so users can install their own speaker to hear the tones.

In your case, I think your board (or the CPU - but I suspect board) has bought the ghost.

 

Bill: I did as you suggested, in your earlier response, and eliminated all extraneous and add-on items and all but one stick of ram. I again attempted to start it. Nothing. I do have a dead MB and will dispose of accordingly. I thank all of you for your assistance and suggestions. I will classify this thread as resolved. Dennis

 

Well, sorry we could not resolve this. But again, a 13 year old board, I think it served you well.

Thanks for the follow-up.

 

Bill: Again, Thanks!