DELL Precision 650 turns on, but shows no signal in monitor?

If you try booting with no RAM installed (video card installed),  no beeps probably means failed motherboard

GOT SIX BEEPS

If you try booting with no video card (RAM installed), no beeps probably means failed motherboard

GOT SIX BEEPS

Changed video card

GOT SIX BEEPS

Did you try all RAM modules in slot 4, or just the one?

TRIED 6 DIFFERENT DIMMS.  ALL FAILED.  IE  A & B LIGHTS YELLOW AND NO BOOT.....BUT, 2 OR 3 OF THEM FLASHED THE INITIAL DELL SCREEN.  ONE BOOTED AS FAR AS HIT F1 TO BOOT OR F2 FOR SYSTEM SET UP.  THEN SAID WINDOWS DID NOT CLOSE PROPERLY HOW DO YOU WANT TO BOOT.  SELECTED SAFE MODE AND THEN IT DIED.

THIS MAKES ME WONDER IF SLOT 4 IS BAD OR THE MEMORY IS BLOWING ONCE IT IS PLACED IN SLOT 4 BECAUSE THE MACHINE WOULD NOT REPEAT THE ABOVE AFTER THIS FIRST PARTIALLY SUCCESSFUL BOOT.

Try this: Put a module in slot 4 and then remove motherboard battery and press/hold power button for ~30 sec. Then reinstall battery. That will make BIOS rescan the hardware and see there's only one module installed. If it still won't boot with any module in slot 4, it could be either motherboard or CPU.

DID NOT BOOT AND I USED A NEW MOTHERBOARD BATTERY

And one last thing: Strip it down to bare essentials: Disconnect all drives except HDD, remove all cards except video, leave RAM module only in slot 4. If still no go, motherboard or CPU...

DID NOT BOOT?

Any suggestions?  

Questions:

Could I put another Intel processor from an older machine in it, this one has a Xeon chip?

How do we know slot 4 is not bad?

How do you eliminate the processor vs the motherboard?

Can I put the processor in the CPU 2 slot while having no processor in slot 1?  Will that tell anything?

Older machines had a jumper to reset the BIOS, I do not find one on this machine.  Is there one?

You're not making this easy...

Are all 6 RAM modules identical? They need to be 512-MB, 1-GB non-ECC or ECC, 266 MHz DDR. And you're not mixing ECC and non-ECC RAM, or exceeding max allowed RAM (4 GB)?

6 beeps is not a valid error code. Beep codes come as three groups, separated by a brief pause and then repeating. So are you hearing 2-2-2 (RAM error), or some other combination that adds to 6, eg 1-2-3, 3-1-2?  You'd expect a RAM error beep code if none is installed.

What happens if you disconnect the hard drive, clear BIOS  by removing the battery and pressing/holding power button for ~30 sec and, after reinstalling the battery, trying to boot from a bootable CD or DVD, eg Dell Windows Reinstallation disk or Dell Resources disk?

Since it -sometimes- gets to the point of showing error messages and even offering Safe Mode, I'm starting to wonder if the PSU is the problem.

Only way to know if the CPU failed is to replace it with a known working CPU. As I read the specs, it's only compatible with Xenon chips so anything else won't work, even assuming some other chip fits in the socket, which it probably won't.

There's a RTCRST jumper on the motherboard. But if system is unplugged and you remove motherboard battery and press/hold power button for 30 sec, BIOS should be reset to the defaults.

see above and another question

Only way to know if the CPU failed is to replace it with a known working CPU. As I read the specs, it's only compatible with Xenon chips so anything else won't work, even assuming some other chip fits in the socket, which it probably won't

What is the risk of damaging the working CPU by placing it in this unit.  I can't afford to have 2 go down.

You're not making this easy...

That my friend, is the state of everything I seem to do

Are all 6 RAM modules identical? They need to be 512-MB, 1-GB non-ECC or ECC, 266 MHz DDR. And you're not mixing ECC and non-ECC RAM, or exceeding max allowed RAM (4 GB)?

All 6 dimms are identical and either came out of this machine or another working p650 that was identically manufactured.  Three are OEM, the other 3 were purchased from Dell.  They all have been in the P650's since they were put into service, so I would assume this should not be an issue

6 beeps is not a valid error code. Beep codes come as three groups, separated by a brief pause and then repeating. So are you hearing 2-2-2 (RAM error), or some other combination that adds to 6, eg 1-2-3, 3-1-2?  You'd expect a RAM error beep code if none is installed.

Only got the beeps when booted with no RAM or when no video card or when video card was swapped out from another machine.  Is does not occur when the memory is changed.  Do you want me to swap the video card again to the the beeping code?

What happens if you disconnect the hard drive, clear BIOS  by removing the battery and pressing/holding power button for ~30 sec and, after reinstalling the battery, trying to boot from a bootable CD or DVD, eg Dell Windows Reinstallation disk or Dell Resources disk?

No Boot.  Quickly goes to orange A and B lights.

Since it -sometimes- gets to the point of showing error messages and even offering Safe Mode, I'm starting to wonder if the PSU is the problem. 

Only got there one time out of 50 or so attempts we have performed so far.

Only way to know if the CPU failed is to replace it with a known working CPU. As I read the specs, it's only compatible with Xenon chips so anything else won't work, even assuming some other chip fits in the socket, which it probably won't.

What about putting it into the other socket, will that yield anything

There's a RTCRST jumper on the motherboard. But if system is unplugged and you remove motherboard battery and press/hold power button for 30 sec, BIOS should be reset to the defaults.

So, is there any other way to do a differential diagnosis?

There shouldn't be a risk  swapping the CPU with known working one. But I'd be inclined to swap the PSU first which is less hassle.

Since it managed to start booting at least once that suggests the CPU  and motherboard might be OK.

Are there instructions in the manual on how to remove the power supply

Page 65.

Got it !... but It's a no go. 

It came up as far as it did that one other time...Hit F1 or F2.  Would not let me hit F1 ( did not have the hard drive attached).  I hit F2 and reset the BIOS clock.  Reattached the hard drive and rebooted and got A to blink for a couple of attempts but then only get A & B yellow....bummer

 :emotion-12:

Are C, D green when A, B are yellow?

That would be a RAM error again. So now go back to putting one module in slot 4, reset BIOS by removing the battery, pressing/holding... And then see if it boots.

If not, then I guess you probably are looking at a motherboard problem...

Are C, D green when A, B are yellow?

YES and I tested the memory in a working machine and it works so it is not the memory.  So that leaves the processor or the board, correct?

How about the other approach of getting the drive to live in another PC...any thoughts?

A follow up:

Hard drive comes up on another computer and so does the memory so it is definitely is not either one of those.

While I am not ready to give up yet....how about a different approach to getting a PC up...I tried to put a clone of the P650 drive into a dimension 6100 and it would not even come up.  If I could get it to come up on another computer I could just use one of those.  Any thoughts or suggestions?   I have not experienced windows not coming up and just putting generic drivers in place, so I am baffled yet again!

Both systems have xp licenses so if i am correct the windows licenses should not be an issue

I don't know what a "dimension 6100" is (no such model listed on Dell's support site). Did you mean Dimension 8100 or perhaps a Studio XPS 8100?

Either way, the Windows installation and drivers on that HDD for a Precision with Xenon processor are very unlikely to work with any system that isn't running a Xenon processor.

You could just clean install Windows for whatever model that other system is using the HDD from the Precision, as long as you install the version of Windows that was licensed by Dell for the other system - or buy a valid product key for whatever version of Windows you want to run on the other system.

EDITED

Sorry dimension 8100. 

I agree a clean install is the best approach.  My challenge would be in getting the proprietary software I have on the 650 load onto a clean system load.  I think I may have a way to do it, but it would take a lot of investigation and time.  So if I could slam it onto another machine it sure would be a heck of a lot easier. 

As long as they're both licensed for the same version of XP, eg Home or Pro.

Except, I don't see that Dell ever offered the D8100 with XP. So did you buy a retail license to use XP on the D8100?