Dell XPS 720 H2C No Boot

LEK-89 · 15 Oct 2010 at 13:18

Dell finally came out to us last week and they replaced the dead motherboard in our machine but I have only just got round to putting everything back together. (Dell guy only took the old motherboard out & put the new one in as I said I would do the rest) I have fitted everything back together but I have also replaced the CPU with a Core 2 Quad Q8300 as my dad is using the original QX6800 in his new home machine for some time while this Dell was down.

Anyway, powered on the machine and I am greeted with all the fans on full blast, all the lights on and their is a small display at the front of the PC which has the digits "1 2 3 4" and also the HDD activity lights etc. but their is no display on the monitor and their are no error beeps either.

After a few seconds the front panel is displaying the lights "1 2 3" only which according to the Dell manual, is a "Another failure has occured" and it only specifies to make sure that all the connectors on the motherboard are connected, all peripherals are connected at the back which they all are.

When the machine is operating normally it should display all of the "1 2 3 4" lights. The light on power button on the machine is also solid green which indicates that power to the whole machine & the cpu health is normal

I have done some testing to try and rectify the problem like removing all the sticks of RAM and testing them individually and without the RAM the motherboard does beep so I know the motherboard is ok.

Also took out all of the graphics cards and it gives an indication if the cards are missing too and also tested them individually, removed the CD & DVD drives etc. and I even removed the CPU and powered the machine and it gave out it's own indication that a CPU was not present too (power button light turns orange) so I know the CPU must be ok.

I am stuck to what else I could try now, has anyone else ever came across this problem or does anyone else have any ideas?

Thanks all - Liam

RJC · 15 Oct 2010 at 13:19

Wonder if the new board can take the new cpu without a BIOS update.

LEK-89 · 15 Oct 2010 at 13:23

RJC said:
Wonder if the new board can take the new cpu without a BIOS update.

That is something that has sprung to mind, at the time when the Dell techie was here as well he said that as long as it is a socket 775 CPU their shouldn't be a problem with having a different CPU on the board.

Thinking about it now, the QX6800 CPU is only a 1066 FSB CPU & this new Q8300 is a 1333 FSB CPU - would this be the problem??

Edit - After a bit of googling, the motherboard in this machine is 1333 FSB compatiable.

Liam

HazardO · 15 Oct 2010 at 13:38

LEK-89 said:
Edit - After a bit of googling, the motherboard in this machine is 1333 FSB compatiable.

Liam

It might still need a BIOS update to support the newer CPU though.

LEK-89 · 15 Oct 2010 at 17:54

HazardO said:
It might still need a BIOS update to support the newer CPU though.

I think that is the conclusion that I have come to.

This afternoon I tested a Pentium D 3.99Ghz (I think it was actually 1066Mhz FSB) and also a Pentium 4 631 but I think that was 800FSB and both of them still did not enable the computer to POST. Though, this time with either CPU's when powering the machine all of the fans operated at a much lower speed and after 10 seconds of powering the machine, their were 2 quick beeps that could be heard from the motherboard but I don't know what what this meant. The "1 2 3" lights on the front were still displayed during both attemps.

So, I think now I will either have to return the CPU back and get a refund or somehow I could try and update the BIOS on the motherboard but how can this be done in this case?

Thanks again - Liam

HazardO · 16 Oct 2010 at 08:53

I don't see how you'll be able to update the BIOS without borrowing a compatible CPU first. You might be able to get you hands on a cheap 2nd hand P4 for the purpose.

LEK-89 · 16 Oct 2010 at 12:49

HazardO said:
I don't see how you'll be able to update the BIOS without borrowing a compatible CPU first. You might be able to get you hands on a cheap 2nd hand P4 for the purpose.

Looks like I may have to borrow the original QX6800 (the one that came with the Dell from new) that is now in my dads new build and do it that way. If it still doesn't work then I reckon it's down to this new board.

Liam

LEK-89 · 18 Oct 2010 at 11:43

Update,

I took a Pentium Dual Core CPU out of another machine this morning and I also removed 1 of the graphics cards out of the machine and it's finally booted up. Looking in the BIOs I have already got the latest BIOS version installed on the new motherboard. I then decided to swap the CPU's round for the new Q8300 one and it's also finally booted on this one too but the BIOS reports that it doesn't recognise CPU! In the BIOS it shows the CPU as "Intel Sample Processor" and with the Q8300 CPU all of the comp fans still run at full blast. With the Pentium Dual Core in the machine it runs totally fine and the BIOS recognises the CPU fine.

Edit - Managed to persuade my dad to swap the old QX6800 out of his current machine with the new Q8300 that is not compatiable with the Dell motherboard as the Q8300 will work with his P5QD Turbo no problem but now once he has the Q8300 in his machine he wants it clocking to 3.0Ghz :eek:

Thanks - Liam