is it my mobo or PSU that is faulty?

Bahney · 28 May 2006 at 17:07

i just bought myself a new pc, put it all together no probs and it worked first time Hurrah! i thought

managed to get windows installed ok and everything was funning fine, i have shut down the pc and now it wont start back up again!

i unplugged the powrer cord flicked the i/o switch a few times and nothing, my mobo has a standby led on it which just flashes.

after leaving it 30min or so...i had to i was getting fustrated!

i went back and noticed the standby led was solid amber and not flashing...odd i thought and pushed the power cable and hey presto worked!

i then had to shut it down again and you guessed it...no power! just a flashing LED, pc is 2 days old.

psu = seasonic s12 500W
Mobo = Lan party NF4 ultra-D

i have checked all the power connectors on the board and they are all in solid, there appears ot be nothing really wrong with it.

any ideas ?

Bahney · 28 May 2006 at 17:38

ok with a process of trial and error of unplugging and re plugging in things and testing i have discovered something very strange!

if i unplug one of my ram strips the standby light goes solid stright away when i turn it on and hey presto my pc boots up!

i have tested both pieces of ram and all 4 ports none of the ports are faulty and neither piece of ram is faulty! but when i have both in the pc it now will not start up???

i have a feeling my psu is not powerful enough, i have unplugged my hard drives and dvd-rw etc and left both pieces of ram installed but still no joy, if i have just my mobo/gfx card plugged in it still wont work until i remove one piece of ram,

here is my full spec

hitatchi deskstar 250gb X2 useing the Sata power cables
athlon 64 4400
mushkin 2gb em3200 (2X1gb)
connect 3D radeon X1900 Xt 512mb
seasonic s12 500W silent atx2.0 (ca-001-ss)
dfi lanparty UT NF4 ultra-d (mb-014-df)
zalman s7000

its all a bit bizare!

xirokx · 28 May 2006 at 17:39

have checked all the power connectors on the board and they are all in solid, there appears ot be nothing really wrong with it.

so all four are plugged in? just wanted to double check...

as its a dfi i believe it has a power on switch on the mobo itself...

take it out the case, just install the cpu, hsf and 1 stick of ram and see if it boots...and stays on...

Bahney · 28 May 2006 at 17:55

i have plugged in the long 20pin power connector, there is a small 4 pin connector next to it and there is a molex type connector and a floppy drive type power connector on the mobo, i have plugged all these in

if i remove one piece of ram it boots up into windows but beeps twice before post, i have checked the mobo manual but there is no beep guide!

any more ideas? i am useing the power switch on the mobo itself while i am trying to fix this.

how strange is this problem? lol

t31os · 28 May 2006 at 18:28

You can google pc beeps, you just need to know which bios you have, which is generally apparent on boot, ie. Phoenix, Award, etc....

Bahney · 28 May 2006 at 20:24

right then, i have put in some ram out of my old pc and hey presto everything works perfectly, starts up etc and everything is perfect.

so i will have to call ocuk on tues and arrange to send this ram back for a replacement Doh!

xirokx · 28 May 2006 at 20:34

This is what I found from the "how to fix it guide" on this forum

2,any,any - Any beeps after 2 indicates bad memory. Run a memory test and replace the RAM (testing exmplained alter on)

definately seems like bad memory mate...

Glad you sorted the problem...

Bahney · 29 May 2006 at 19:59

it is defenatly the ram that is at fault.

before i call ocuk tomorow and arrange for it to be sent back could someone please confirm that the psu i have will be able to power my rig ? it isnt just a lack of power? i have removed devices such as hard drives and cd-roms etc and still no joy so i am 99% sure it is faulty ram but i still have that thought in my head that when i have this ram in the pc it may be under powered.

i just dont want to send it back for a replacement and have the replacement be faulty as well, lol

Bahney · 30 May 2006 at 12:03

anyone?

is the psu i have powerful enough ?

split · 30 May 2006 at 14:34

If you search the DFI forums in the Nforce4 section for 'Seasonic', you'll find threads like this.

It seems some boards just have a problem with new high-efficiency psus.

quadboi · 30 May 2006 at 14:38

split said:
If you search the DFI forums in the Nforce4 section for 'Seasonic', you'll find threads like this.

It seems some boards just have a problem with new high-efficiency psus.

Lol problems with them ! Thats crazy, why aren't the mobo guys eco-friendly

I have a Seasonic 600w S-12 on the asrock 939 dual sata.

split · 30 May 2006 at 15:28

It's not only DFI or seasonic tho.
If you look say here...

TIP: if you experience problems with Antec Neopower and Truepower PSU's and also with PowerStream PSU's, try Bios 1.37 and turn the PSU off after you shut down, seems to help as well

People found a way over that was to use a cheaper PSU as they are not as fussy.
I know DFI's seem to have had a cold boot issue, but others have it. (not really a cold boot issue tho)

Think they are saying it's caused by "Too low a 12V load on startup is the most common cause of a high efficiency PSU not starting with the kind of low power minimalist system that many SPCR readers build".

Modern PSU's maybe are more efficient, but they seem to have this no boot issue

RhythmAce · 30 May 2006 at 17:30

The lower posts here are spot-on. It's the PSU that's the culprit. Because the 12v rail is split, only half the amperage goes down each rail. These SeaSonic PSUs are designed for Intels. You need a PSU without the twin 12v rail.

Don't get a cheap one, though - cheap PSUs will just lead to more problems down the line, if you ask me. Plus it won't be as beautifully quiet. Just get a really decent one with a single 12v rail. If such a thing exists - I haven't looked

split · 30 May 2006 at 17:56

RhythmAce said:
The lower posts here are spot-on. It's the PSU that's the culprit. Because the 12v rail is split, only half the amperage goes down each rail. These SeaSonic PSUs are designed for Intels. You need a PSU without the twin 12v rail.

Don't get a cheap one, though - cheap PSUs will just lead to more problems down the line, if you ask me. Plus it won't be as beautifully quiet. Just get a really decent one with a single 12v rail. If such a thing exists - I haven't looked

I wish it was that simple.

The OCZ's 520 (one at least) I referred to in my post has following spec.
Specs:
AC input: 100-120 / 200-240Vac, 10/6A, 60/50Hz
+3.3V: 28A
+5V: 40A
+12V: 33A <single rail

People still had that issue with that PSU, and the Antec truepower only has a single 12volt rail.

According to this...
I've heard that the powerstream can enter an overvoltage protection session.

Almost seems like it's the protection on modern PSU's is causing the problem, but not everybody gets it.

This is a real pain on a new build if you haven't got another PSU you can try.

RhythmAce · 30 May 2006 at 18:38

Wow - thanks for that, split. This really is a pain! Do you have any experience on what PSU's would be suitable (600w+)? I don't want to fall foul of the same problem with another PSU!

Edit: The OCUK prebuilds with AthlonX2/A8N-SLI (same as mine) come with Tagans, so I guess that must be OK...? Despite the fact it's still twin rail...

Of course I also have the problem of ensuring the leads are long enough for my Antec P180 case...

Man, I'm so confuddled I think my head might explode.

split · 31 May 2006 at 01:48

Have a read of this.

Esp the bit where he says...
Irregardless of the current draw by the Expert board, the same issue has been experienced on dozens of other boards. Units from ABit, ASUS, MSI and Tyan all experience the same issue if you have them running on the newer "high power" PSU's.

Have to say I've not seen a great deal of this on ASUS boards on the web, but they don't have a forum dedicated to ASUS like DFI or MSI. (it's on those forums you see loads of them)

A very high % of users get no problems at all tho which makes it hard to recommend anything.

I have read on the DFI forums..
Seasonic as had problems from day one. They even went as far as to blame the DFI boards but when it was happening with just about every other high performance motherboard they modified their design according to emails sent to customers.

But you'll find many people using them with no problems at all.
I've also read they are making modifications to PSU's (Version1 and 2 etc) to stop the "switch bounce".

It's mega annoying tho, and if you send the PSU back as "not working", unless the test it on your rig it will prolly work.
Also makes it nigh on impossible to "recommend" anything

Added..
This is how you test a PSU, and if yours is a 24 pin one you use these..