Possible PSU problem.

[neoboy]

Right I think I better start from the beginning. Around 6 months ago I started having problem with random restarts and crashes. What I done then is take out 2 RAM sticks (out of 3), disconnect 1 DVD writer and 1 HD as well underclocking the CPU to 1.2 GHZ from 2.08 and then the PC became stable again. So I pinned the problem down to PSU.

However, due to lack of money and will to actually do anything about it (since it was running smoothly again) I just left it at that. About a month ago though my graphics card packed in. I'm now getting lines all over the screen in games, desktop and any other application (including BIOS screen). I'm guessing that's the memory chips on my 9800 Pro gone. So at this point the PC is still stable I just can't read anything on the screen anymore or play games.

So as my pay came in I bought myself a second hand 470W Enermax noisetaker from MM. The guy said it was a RMA replacement and he never used it. Only problem I encountered when installingt it is that the PSU is 12V ATX 2.0 format hence has a 24 pin cable and my motherboard has a 20 pin socket and I couldn't just plug the 24 pin in the right way since the 4 pin socket on the motherboard was right next to and it didn't just clip of either so I had to buy a 24 to 20 adapter from a local PC shop.

I bought that and when tried to start the PC the thing would go past the BIOS screen but just wouldn't make it to the Windows screen. I took out 2 memory sticks and it loaded up, logged into windows, but then the PC just cut off after 20 seconds. When I pressed the power button the thing just came on for a fraction of a second and then cut out again. Had to unplug it from the electricity wait for about a minute and then it would log into windows and then cut off again. Then it would only turn on for a fraction of a second and so on...

Now I have a few theories, however, still quite puzzled:

1) The 24 to 20 pin adapter I got for 3 quid is faulty (my mate has a 24 pin PSU and 20 pin motherboard, trying to get hold of him to see if that is the case).

2) My motherboard or other components are not compatible with 12V 2.0 format PSUs (although I thought it was all backwards compatible).

3) Possibly all those protection shutdown systems that Enermax boast about detect some sort of electrical distortion/fluctuation/whatever else in my "on the way" graphics card? Although that seems rather far-fetched to me.

4) The PSU is simply buggered. I also noticed in my mobo bios health screen that -5 rail is simply saying 0 as opposed to my old PSU which was well within the 5 region (other rails seem perfectly fine).

Here are some specs for my PC:
AMD 2800+ Barton
Crucial 3x512 DDR400 memory sticks
MSI K7N2 DELTA ILSR motherboard
Sapphire 9800 Pro graphics card
and the PSU in question is 470W Enermax Noisetaker EG475AX.

P.S. Also note that since installing the new PSU I put the old one back in and it's been running smoothly with that in.

Any help on the matter would be appreciated.

 

[acharris]

Hi, I can't really help you much, but I wouldn't worry about the -5v rail showing 0, as the only that is used is +5v and not -5v, so that reading 0 is no problem at all. If you have access to a multi meter then you could measure the voltages your self across the rails by the following methods:

Find a molex connector and meaure 12v on the yellow lead on the molex and the 5v reading on the red lead that goes into the molex connector and see what readings that would give you, as you can tell if it is giving out life or not.

Sounds like a power issue to me, but I thought that a 24 pin would plug into a 20 pin and you would have just a overhang, as you can plug a 20 pin plug into a 24 pin socket and leave the last 4 free on some older systems, as I am using that setup on a gigabyte board with a 939 A64 2 ghz and 6600 gt PCI-E card.

Anthony

 

[neoboy]

Sounds like a power issue to me, but I thought that a 24 pin would plug into a 20 pin and you would have just a overhang, as you can plug a 20 pin plug into a 24 pin socket and leave the last 4 free on some older systems, as I am using that setup on a gigabyte board with a 939 A64 2 ghz and 6600 gt PCI-E card.

Yeah that was the original idea, I done the same when I build a PC for my friend, but the problem I had with my motherboard is that the space between the 20 pin and 4 pin connections on it is about 2 mm so I had to get the adapter.

Here's a pic of my mobo layout as you can see the space between the 2 is too small for any overhand.

 

[acharris]

I can see that, can't really see the adaptor being faulty as it is not a lot that can be wrong be wrong with them, and I have used a few 20 to 24 pin adaptors for people and have never had a problem with them.

Also when you say smoothly, is it now running with all sticks of RAM, normal CPU speed, and all drives connected under the old PSU or still in the state of 1 stick, lower CPU speed and drives disconnected, as if 2 PSU gives a similar fault of an unstable PC, then it maybe be time to look into other area of problems like the motherboard itself dying.

The board might have a power problem and can't run stable enough to power the AGP slot to run the 9800 pro as it is now getting worse, as not enough power will cause the same effect on GFX as a faulty card itself.

See if you can test further by swapping boards and plug your stuff into a different board and see if it all runs on the both PSU's stable. Good Luck.

Anthony