New PC build will not post or give video output

M

Martin C

I have finally put together a brand new PC build using the following
components

Antec TX640B case with Antec 400W SmartPower PSU
ASUS A8N5X motherboard
AMD Athlon 64 3500 processor
1GB Corsair TwinX 3200 DDR RAM (2x512MB matched)
200GB Seagate Barracuda SATA HDD
Floppy Disc drive
Lite-On DVD RW
Leadtek GeForce 6800GS PCI-Express video card

When I try to power up the PC, I get no POST and nothing appears on the
screen.
The keyboard lights flash briefly when I turn on the Antec power supply
itself (the switch at the back of the PC on the PSU), but they do not flash
when I turn on the PC itself.

I have tried the following so far:
a) All unnecessary devices have been unplugged completely (Floppy, HDD,
DVD) - problem persists
b) Disconnected the keyboard - expecting to receive an error - still no POST
or display.
c) Have reseated and reconnected the video card repeated - problem persists.
d) Have reset the CMOS - no change.
e) Have taken out one of the DIMM sticks and have tried swapping them as
well. No change.

I assume this means that the memory is probably ok.

The box in which the graphics card came states that it needs a 350W minimum
PSU, so my 400W Antec should be ok.

If the graphics card is broken, would I still get a POST bleep? I have
checked the speaker lead in the case and it seems ok. Yet I have yet to hear
any sort of bleep from the speaker, so I don't know if it is trying to tell
me something, but I can't hear it, or not.

Unfortunately, as this is a completely new build, there is nothing in my old
PC that I can use to replace to try things out (it really was an old PC).

If anyone can help me out with this, I will be so grateful as I have run out
of ideas other than trying to send back each component separately until I
can get something to work. That works out expensive in postage and time
consuming.

What is more likely to be at fault here, PSU, CPU, Graphics card or
something else?

TIA
Martin
 
D

Dave

Martin C said:
I have finally put together a brand new PC build using the following
components

Antec TX640B case with Antec 400W SmartPower PSU
ASUS A8N5X motherboard
AMD Athlon 64 3500 processor
1GB Corsair TwinX 3200 DDR RAM (2x512MB matched)
200GB Seagate Barracuda SATA HDD
Floppy Disc drive
Lite-On DVD RW
Leadtek GeForce 6800GS PCI-Express video card

When I try to power up the PC, I get no POST and nothing appears on the
screen.
The keyboard lights flash briefly when I turn on the Antec power supply
itself (the switch at the back of the PC on the PSU), but they do not
flash
when I turn on the PC itself.

I have tried the following so far:
a) All unnecessary devices have been unplugged completely (Floppy, HDD,
DVD) - problem persists
b) Disconnected the keyboard - expecting to receive an error - still no
POST
or display.
c) Have reseated and reconnected the video card repeated - problem
persists.
d) Have reset the CMOS - no change.
e) Have taken out one of the DIMM sticks and have tried swapping them as
well. No change.

I assume this means that the memory is probably ok.

The box in which the graphics card came states that it needs a 350W
minimum
PSU, so my 400W Antec should be ok.

If the graphics card is broken, would I still get a POST bleep? I have
checked the speaker lead in the case and it seems ok. Yet I have yet to
hear
any sort of bleep from the speaker, so I don't know if it is trying to
tell
me something, but I can't hear it, or not.

Unfortunately, as this is a completely new build, there is nothing in my
old
PC that I can use to replace to try things out (it really was an old PC).

If anyone can help me out with this, I will be so grateful as I have run
out
of ideas other than trying to send back each component separately until I
can get something to work. That works out expensive in postage and time
consuming.

What is more likely to be at fault here, PSU, CPU, Graphics card or
something else?

TIA
Martin

Check and double-check and triple-check your connections betwen the case and
the mainboard. Pay special attention to the power and reset wires, make
SURE they are on the right pins. If they are off by one (and those
connectors are hard to see), then nothing will happen when you press the
power switch.

If all connections are good, most likely cause of your problem is the PSU,
even though it is new. It doesn't matter if you see lights on the keyboard
.. . . LEDs are very forgiving of low voltage. -Dave
 
B

beenthere

Martin C said:
I have finally put together a brand new PC build using the following
components

Antec TX640B case with Antec 400W SmartPower PSU
ASUS A8N5X motherboard
AMD Athlon 64 3500 processor
1GB Corsair TwinX 3200 DDR RAM (2x512MB matched)
200GB Seagate Barracuda SATA HDD
Floppy Disc drive
Lite-On DVD RW
Leadtek GeForce 6800GS PCI-Express video card

When I try to power up the PC, I get no POST and nothing appears on the
screen.
The keyboard lights flash briefly when I turn on the Antec power supply
itself (the switch at the back of the PC on the PSU), but they do not
flash
when I turn on the PC itself.

I have tried the following so far:
a) All unnecessary devices have been unplugged completely (Floppy, HDD,
DVD) - problem persists
b) Disconnected the keyboard - expecting to receive an error - still no
POST
or display.
c) Have reseated and reconnected the video card repeated - problem
persists.
d) Have reset the CMOS - no change.
e) Have taken out one of the DIMM sticks and have tried swapping them as
well. No change.

I assume this means that the memory is probably ok.

The box in which the graphics card came states that it needs a 350W
minimum
PSU, so my 400W Antec should be ok.

If the graphics card is broken, would I still get a POST bleep? I have
checked the speaker lead in the case and it seems ok. Yet I have yet to
hear
any sort of bleep from the speaker, so I don't know if it is trying to
tell
me something, but I can't hear it, or not.

Unfortunately, as this is a completely new build, there is nothing in my
old
PC that I can use to replace to try things out (it really was an old PC).

If anyone can help me out with this, I will be so grateful as I have run
out
of ideas other than trying to send back each component separately until I
can get something to work. That works out expensive in postage and time
consuming.

What is more likely to be at fault here, PSU, CPU, Graphics card or
something else?

TIA
Martin
On top of what you`ve already been told.
Make sure the Mboard isn`t touching down on the case !
Is the Grfx card powered ?.
 
M

Martin C

Wow! Thanks for the rapid responses. I was just about to add some extra
details that I had originally missed off.

The power and reset switches work ok.
The power starts up each of the fans I have - CPU, Case fan, Northbridge
fan, Graphics card fan. The PSU fans work as well.
The PCI-Express power connector is plugged into the graphics card directly
from the PSU.
The Led on the front of the case lights up when the power switch is pressed
and the led on the motherboard lights when the PSU is on.

I have checked, and the motherboard is not touching the case anywhere.

Thanks for the responses, but unfortunately, they were not the problem. Any
further ideas.

Martin
 
C

Chris Hill

I have finally put together a brand new PC build using the following
components

Antec TX640B case with Antec 400W SmartPower PSU
ASUS A8N5X motherboard
AMD Athlon 64 3500 processor
1GB Corsair TwinX 3200 DDR RAM (2x512MB matched)
200GB Seagate Barracuda SATA HDD
Floppy Disc drive
Lite-On DVD RW
Leadtek GeForce 6800GS PCI-Express video card

When I try to power up the PC, I get no POST and nothing appears on the
screen.
The keyboard lights flash briefly when I turn on the Antec power supply
itself (the switch at the back of the PC on the PSU), but they do not flash
when I turn on the PC itself.

I have tried the following so far:
a) All unnecessary devices have been unplugged completely (Floppy, HDD,
DVD) - problem persists
b) Disconnected the keyboard - expecting to receive an error - still no POST
or display.
c) Have reseated and reconnected the video card repeated - problem persists.
d) Have reset the CMOS - no change.
e) Have taken out one of the DIMM sticks and have tried swapping them as
well. No change.

The machine should beep with no video and no ram, try that. A hard
drive and floppy aren't necessary yet, unplug everything, just have
speaker, psu and on/off connected to the mainboard with cpu installed.
If you get nothing, then you're looking at cpu, psu, or mainboard.
I'd guess either psu or mainboard. If you've ever thought about
building another machine, it might be time to order the parts, that
way you'd have something to test with.
 
D

dawg

Did you check the CMOS jumper.It may be in the wrong position Just one of
those little things that cause a failure to boot.
 
H

hrdtd

You've already tried all the more common obvious items. so it time to try
some of the more remote possibilities...

Each new system I build, I first start out with all the basic components
outside the case, sitting on the bench.

start with just the MB, the CPU/HSF, the ram. a known video board & monitor,
and if need be, a small speaker you can attach to the MB itself to listen
for error beeps.

Fire it up by either manually shorting out the pins on the MB that normally
go to the front panel power switch, or by using a power button from an old
case.

If the video displays on the monitor check to see it counts the right amount
of memory and CPU.

Only if I get that far do I proceed to mount the MB in the case.

I mention this because it's 'possible' although not as likely with todays
MB's as it was with older MB's that where the MB mounting posts meet the MB,
older MB's required you to use a small insulating washer on at least a few
of the studs so the stud wouldn't short out some paths near the hole on the
MB.

Modern MB's are usually designed such that the insulating washers are no
longer needed and in some case must NOT be used.

It's 'possible' that you installed one of the MB standoffs in the wrong
position in the case, and instead of it aligning with the mouinting hole,
it's touching somewhere else on the MB causing your problem.
 
C

Charlie Wilkes

Wow! Thanks for the rapid responses. I was just about to add some extra
details that I had originally missed off.

The power and reset switches work ok.
The power starts up each of the fans I have - CPU, Case fan, Northbridge
fan, Graphics card fan. The PSU fans work as well.

Do you have the CPU plugged in? That's kind of basic, but lots of
people miss it, especially as older machines didn't have a separate
CPU power source.

Charlie
 
M

Martin C

Further update.
I have checked the CMOS jumpers and they are correct.
I have tried the motherboard outside of the case (resting on cardboard) with
only the CPU and fans powered. I did not even have any memory or video card
present. I had the lead to the speaker attached.
I still get no POST.

I checked the power supply on one of the Molex connectors and found that I
am getting the following voltages (with no load)
5.02V on the 5V line
12.42V on the 12V line.

Should the 12V line be that high? Is that a problem?

One other point of possible interest I should note:
With the PC turned on all the fans run and relevant leds are lit. When I
hold in the power switch for more than 4 secs, the front power led on the
case goes out (implying that the system is turned off?) but all the fans
(CPU, Case, PSU etc) are still running. The only way I can stop these is to
turn off the PSU itself with its own switch at the back. Does this indicate
a problem with the PSU or something else.

Thanks for all the help I have been given so far.

Martin
 
C

Chris Hill

Further update.
I have checked the CMOS jumpers and they are correct.
I have tried the motherboard outside of the case (resting on cardboard) with
only the CPU and fans powered. I did not even have any memory or video card
present. I had the lead to the speaker attached.
I still get no POST.

I checked the power supply on one of the Molex connectors and found that I
am getting the following voltages (with no load)
5.02V on the 5V line
12.42V on the 12V line.

Should the 12V line be that high? Is that a problem?

One other point of possible interest I should note:
With the PC turned on all the fans run and relevant leds are lit. When I
hold in the power switch for more than 4 secs, the front power led on the
case goes out (implying that the system is turned off?) but all the fans
(CPU, Case, PSU etc) are still running. The only way I can stop these is to
turn off the PSU itself with its own switch at the back. Does this indicate
a problem with the PSU or something else.

I'm going to have to guess mainboard. Really is no way to be
absolutely sure except by swapping parts.
 
H

hrdtd

I agree, it's sure sounding like a bad MB.

Chris Hill said:
I'm going to have to guess mainboard. Really is no way to be
absolutely sure except by swapping parts.
 
P

Philip Nicholls

Further update.
I have checked the CMOS jumpers and they are correct.
I have tried the motherboard outside of the case (resting on cardboard) with
only the CPU and fans powered. I did not even have any memory or video card
present. I had the lead to the speaker attached.
I still get no POST.
[deleted remainder of post]

Have you tried re-seating the CPU and HS/fan?

Remove the CPU from the socket and check the pins. Do any look a
little bent?

Re-seat the CPU, double checking to see that it is complete seated.
With the Athlon64 processes this can be difficult to confirm.

----------------------------
Phil Nicholls

"As will be all too evident when we examine the creationist position in detail, their arguements are devoid of any real intellectual content."
[sentence following the bit Laurie likes to post from The Monkey Business, by Niles Eldredge.
-----------------------------
 

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