New build wont run

[Ultra Violent]

Just finished a new build for my hard up sister. Basically C2D 1.86, Asus P5B 2*512MB, CD/DVD + HD, 450W and 7900GS.

On power up everything seems to get power, all fans (mother board, cpu, case) run, mother board light comes on cd/dvd will open close. But no bios beeps or output to the screen.

A bit stuck on how to debug, and help greatfully receieved.

[Trooper2]

Is the monitor plugged into the Motherboard instead of the video card, I did that once.

[Ultra Violent]

no onboard graphics with this mother board. The bloody thing wont even post.

[Zod]

sounds like a dead motherboard. I had three dead Asus A8N-SLI Premiums in a row.

[ThePassenger]

Take it from the top. Start making sure all the cables are in place and cards pushed down. If that doesn't work, try removing the HDD cables from the mobo (and their power connectors). Pull the RAM out of the system and power on.

It should now beep.

If not RMA the mobo.

[Roy the Boy]

Make sure your memory is seated correctly as faulty or loose memory modules can give those symptoms. Also, I'd check the memory is compatible with your motherboard if you haven't already.

[.Adam.]

When I built my last system, I forgot to plug in the extra power connector on the motherboard and got the same symptoms.

[SLacKer]

Do a bios reset with the MB jumper this usually gives it a kick

[Ultra Violent]

How does one do the MB reset with the jumpers?

Also will it post with no ram in?

Edited by Ultra Violent on Wednesday 30th May 19:29

[spitfire-ian]

It will start up with no ram and then tell you in no uncertain terms that is has none. Can't remember if it's a series of long beeps or lots of short ones but someone will tell you I'm sure.

[Ultra Violent]

OK, with no RAM I get a series of short beeps...

[malman]

Looks like a ram problem - try one stick at a time in different slots (if possible some boards don't like this). Make sure its seated properly and the catches lock in. Double/triple check you have the correct ram (speed etc)

[spitfire-ian]

malman said:

Looks like a ram problem - try one stick at a time in different slots (if possible some boards don't like this). Make sure its seated properly and the catches lock in. Double/triple check you have the correct ram (speed etc)

Yup, if the board is shouting how it hasn't got any ram then the board should be fine.

[sadako]

Off the wall thought here. Is the PSU supplying enough? It the supply new or an old possibly dodgy one?

Edited by sadako on Wednesday 30th May 20:56

[Tunku]

Another off the wall thought. Have you plugged a power connector into the GS7900? Mine needed that to run properly.

[Ultra Violent]

OK, stick of RAM was duff. All else seems fine.

[tigger1]

So it's working now then?

Worst two mistakes (for annoyance factor) I've made were: -

1) Not moving the Mobo jumper from the reset to the normal position - wouldn't start up, behaved like a dead board, until I spotted it.

2) Plugging the CPU fan into the board fan slot. Lots of beeping saying that CPU fan wasn't present, despite the fact I could see it working.

[Ultra Violent]

Yes all working now, thanks.

[ThePassenger]

Ultra Violent said:

Yes all working now, thanks.

Always a good trick to pull the RAM. Won't post but will scream like blue murder Glad it's going... all be it on half power until the module is replaced

[Ultra Violent]

OK, so have 2 512MB stick now, But....

They are PC2-6400 (OCZ2p800512), but in the BIOS the machine wont run unless I set the RAM speed to 533mhz. It wont even run if I set it to AUTO.

In CPU-Z, on the SPD screen, it shows the max memory bandwidth as PC2-6400(400), i.e. 400 mhz.

I know least about memory, so any help as always...