Possible monitor trouble?

[DontSayBanana]

I'd try a different PSU first but it's something I have on hand, you might not.

IIRC correctly you have an insane amount of ram, try reducing it to see if anything happens.

10GB of RAM is hardly insane.

No Mac Pro compatible PSU on hand.  Taking out some RAM is pretty trivial so I could give that a try.

I'll take a quick look, but I'm almost certain it is not a blown capacitor.  For whatever reason the monitor is being forced into sleep mode - not that it isn't receiving an image at all.  When I power the monitor up I can see a perfect screen image - for all of one second, before the monitor goes back to sleep.

A blown capacitor doesn't necessarily mean no power to the card at all, but yeah, defective capacitors seem to be a thing of the past- that doesn't include damage from surges, though.  All those capacitors and resistors are there to get it to specific voltage within a really small tolerance range; it could be any electrical damage to the card- capacitors, resistors, voltage regulator... another possibility is a burnt-out fan; a lot of cards will stay in standby if the fan isn't working to prevent heat damage.

[grumbler]

10GB of RAM is hardly insane.

No Mac Pro compatible PSU on hand.  Taking out some RAM is pretty trivial so I could give that a try.

I'll take a quick look, but I'm almost certain it is not a blown capacitor.  For whatever reason the monitor is being forced into sleep mode - not that it isn't receiving an image at all.  When I power the monitor up I can see a perfect screen image - for all of one second, before the monitor goes back to sleep.

Could it be overheating?  Have you cleaned out the air intake and exhaust on your vid card cooler?

[Barrister]

10GB of RAM is hardly insane.

No Mac Pro compatible PSU on hand.  Taking out some RAM is pretty trivial so I could give that a try.

I'll take a quick look, but I'm almost certain it is not a blown capacitor.  For whatever reason the monitor is being forced into sleep mode - not that it isn't receiving an image at all.  When I power the monitor up I can see a perfect screen image - for all of one second, before the monitor goes back to sleep.

Could it be overheating?  Have you cleaned out the air intake and exhaust on your vid card cooler?

I haven't opened the case.  I've had cards fail before and the symptoms were nothing like this, but it certainly couldn't hurt to clean out the computer.

[Barrister]

Cleaned out the dust.  Removed some RAM - symptoms are identical.

Took out the vid card - couldn't see much due to the large plastic shroud, but nothing obviously out of order.  Same with a visual inspection of the motherboard.

This is about as far as I can take this myself.  Taking it to an Apple authorized shop tomorrow.  Heading out of town on Thursday anyways, so hopefully they can fix it fairly cheaply before I get back.

[viper37]

so hopefully they can fix it fairly cheaply before I get back.

"cheaply" and "Apple"?  Well, I suppose you do believe in miracles.

[Barrister]

so hopefully they can fix it fairly cheaply before I get back.

"cheaply" and "Apple"?  Well, I suppose you do believe in miracles.

The Apple Certified technician couldn't find anything wrong with my machine either.  Cost me $60.

So I tested two different monitors, and both showed the same symptom.  And apparently it's not a problem with the Mac itself.

But I just had a eureka moment.

The only common element when I tested both monitors was the DVI cable.  And in fact when I went to hook up this old POS Dell that was sitting in the closet (which only has a VGA out, not DVI) I initially went to use a DVI -> VGA adaptor using the same cable, and I couldn't get a signal.  But I didn't think anything of it, as I just grabbed a simple VGA cable I had sitting in a big box of miscellaneous computer stuff.

I'm 99% sure I have a bad DVI cable.

As soon as the baby wakes up, we're off to a computer store.   

[Barrister]

Well fuck, it isn't the DVI cable.

I'm going to get methodical about this.  Try every possible combination of components to see if I can isolate where the problem is.

[Barrister]

So I'm still trying to match up why the Mac repair shop couldn't find any problem, but I clearly do.

I wonder if the problem is the DVI out from my graphics card.  The Apple branded 5770 has both a mini-DP and a DVI connections.  I don't have a mini-DP monitor, so I've only used the DVI.  Maybe the repair shop only connected using mini-DP?



Any suggestions would be most appreciated by the way.

[derspiess]

So I'm still trying to match up why the Mac repair shop couldn't find any problem, but I clearly do.

I wonder if the problem is the DVI out from my graphics card.  The Apple branded 5770 has both a mini-DP and a DVI connections.  I don't have a mini-DP monitor, so I've only used the DVI.  Maybe the repair shop only connected using mini-DP?



Any suggestions would be most appreciated by the way.

I was going to suggest maybe a messed-up DVI port. 

Btw have you tried swapping in a different video card yet?  Even if you have to buy an el cheapo card to do it, it might be worth doing, assuming you can find one that is Mac-compatible.

edit: or get one of these puppies to hook up your monitor to the mini-display port.

[Barrister]

So I'm still trying to match up why the Mac repair shop couldn't find any problem, but I clearly do.

I wonder if the problem is the DVI out from my graphics card.  The Apple branded 5770 has both a mini-DP and a DVI connections.  I don't have a mini-DP monitor, so I've only used the DVI.  Maybe the repair shop only connected using mini-DP?



Any suggestions would be most appreciated by the way.

I was going to suggest maybe a messed-up DVI port. 

Btw have you tried swapping in a different video card yet?  Even if you have to buy an el cheapo card to do it, it might be worth doing, assuming you can find one that is Mac-compatible.

edit: or get one of these puppies to hook up your monitor to the mini-display port.

When in doubt, go back to square one.

I retested both monitors, and both computers (the Mac Pro and an old POS Dell).  My initial suspicion had been a bad monitor, but I know I couldn't get a signal from the Mac to the older monitor.  But when I went back today, now I can get the old monitor to work, and can't get the new monitor to work on either computer.

So as it's only a year old, I get to fight with Samsung over warranty.  Of course I seriously doubt I kept my old receipt - but it's supposedly a 3 year warranty...