Gx620 No Post

[smarterzippo]

hi to all

this is my 1st time here, hope someone can help.

I've a dell gx620 sff which was all good until i pulled the VGA cable from the monitor, the instant i did this the cpu started fast clicking sounds and the the fan went crazy,
Now after a hard shutdown i have the same noises and nothing else the mobo will not do a post and i have a solid amber light on the power button!
I've tryed a know good psu, and tryed my cpu in an other machine so its def the mobo.

firstly can pulling the monitor lead do this? and how?

and

secondly can i repair the mobo?

any help very much appreciated.

Jon

[370forlife]

Re: Gx620 No Post

You mean you unplugged the monitor cable from the computer while it was running? It shouldn't do anything to the computer in that case, unless you shorted some pins when you pulled out the cable.

[PCBONEZ]

Re: Gx620 No Post

Monitors Are Not Hot Swap.

[PCBONEZ]

Re: Gx620 No Post

Onboard video comes from the main chipset.
If you do not have an add-in video card you may have killed the motherboard's main chipset by way of a voltage spike.

.

[smarterzippo]

Re: Gx620 No Post

You mean you unplugged the monitor cable from the computer while it was running? It shouldn't do anything to the computer in that case, unless you shorted some pins when you pulled out the cable.

yess i pulled the cable while she was running,

[PCBONEZ]

Re: Gx620 No Post

Oops!

The outlook isn't good.
Couple things to try to see if there is any life there:

Reset the CMOS. Should be a jumper somewhere to do that.
[Have it unplugged from AC when you do this.]

You might try an add-in video card to see if you get any display at all.

Inspect board for any small parts that look fried, cracked, burned.

.

[smarterzippo]

Re: Gx620 No Post

Oops!

The outlook isn't good.
Couple things to try to see if there is any life there:

Reset the CMOS. Should be a jumper somewhere to do that.
[Have it unplugged from AC when you do this.]

You might try an add-in video card to see if you get any display at all.

Inspect board for any small parts that look fried, cracked, burned.

.

yea i have tried resetting the cmos using the jumper. and cant see any obvious components which are fried, its not looking good. !

[midibob]

Re: Gx620 No Post

Hi Jon,
With all the 620's I've repaired so far that is the original fault, fan goes full blast with the orange led. Now it could just be coincidence that it failed when you unplugged the monitor although I must admit it does seem unlikely.

Anyway,
Usually I have found on these boards that one or both of the 820uF caps has vented (the ones under the hard disk) but not always. On all the boards there were quite a few of the 220uF caps that had gone high ESR around that area and some even o/cct! Once replaced the boards work OK again so might be worth investigating. I change these as a matter of course along with the 820's.

Checkout the GX620 thread a bit further down.

Good luck
Bob

[smarterzippo]

Re: Gx620 No Post

Hi Jon,
With all the 620's I've repaired so far that is the original fault, fan goes full blast with the orange led. Now it could just be coincidence that it failed when you unplugged the monitor although I must admit it does seem unlikely.

Anyway,
Usually I have found on these boards that one or both of the 820uF caps has vented (the ones under the hard disk) but not always. On all the boards there were quite a few of the 220uF caps that had gone high ESR around that area and some even o/cct! Once replaced the boards work OK again so might be worth investigating. I change these as a matter of course along with the 820's.

Checkout the GX620 thread a bit further down.

Good luck
Bob

hey midibob

cheers for the info i was looking at the thread you mention is this the same for the sff 620's as i can't seam to locate the 820's

[midibob]

Re: Gx620 No Post

I hope we're talking about the same board? I did attach a picture in the other thread so let me know if it's not the one you're talking about. Better still post one of yours.

Cheers
Bob

[370forlife]

Re: Gx620 No Post

Monitors Are Not Hot Swap.

then my video card must have exploded like, 70 times by now, because I just unhook my computer from my monitor to plug in my 360, and I've had no troubles.

[smarterzippo]

Re: Gx620 No Post

I hope we're talking about the same board? I did attach a picture in the other thread so let me know if it's not the one you're talking about. Better still post one of yours.

Cheers
Bob

here is the pic of my gx620 sff mobo

[370forlife]

Re: Gx620 No Post

BTX layout, like most new dells.

Is it me or are those rubycons and OScons?

[smarterzippo]

Re: Gx620 No Post

yes to oscons

[PCBONEZ]

Re: Gx620 No Post

then my video card must have exploded like, 70 times by now, because I just unhook my computer from my monitor to plug in my 360, and I've had no troubles.

You've been lucky.
One of these times it will blow something out.
You'll be a happy camper that day.

.

[Wizard]

Re: Gx620 No Post

I plug hot on the VGA port. DVI as well but I usually do not, since the DVI and HDMI utilize the HDCP and best kept connected till powered off.

Cheers, Wizard

[PCBONEZ]

Re: Gx620 No Post

VGA uses DCC for configuration and it's not Hot-swappable.
Go ahead and burn out your gear.
I really don't care.

[smarterzippo]

Re: Gx620 No Post

Right so we've come to the conclusion that pulling the vga can kill the mobo- we'll most of us....--!

wot has actually fried and is it due for the trash can??

cheers jon

[midibob]

Re: Gx620 No Post

A different board indeed. You'll have to excuse me as I just thought the boards I knew were SFF, at my age even the bigger ones look pretty small to me

As I haven't worked on these then I'll stand by the more knowledgeable comments of the other contributors.
As these boards are probably not so old then there may not be a caps problem but if it were me I'd still be looking at those smaller caps clustered around the middle especially if they're only 85c ones as in the larger boards.
Might be worth checking with an ESR meter (out of circuit) as you've got nothing to lose.

Good luck
Bob

[PCBONEZ]

Re: Gx620 No Post

GX620 comes in SFF and USFF.
USFF = Ultra Small Form Factor.

If it's like earlier series then:
USFF has an external power brick
SFF has an internal power supply

.