Resolved G5 black screen, no chime, nothing...

[1042686]

Thanks Rhian. I never knew about thermal paste or daughter cards before... I was planning I'd try reseating the processor but since everything seems pretty fine with just one processor I don't know how soon I'll be motivated now (I also wonder how I'm gonna get a couple of those screws back in ;D )... but the paste thing does sound like a good idea.

Paste is a great idea on a 15 year old computer I think. I've used both Antec F7 & Arctic Silver 5 to good effect. I'm pretty sure thermal pads can also be used however I do not know the thickness that would be needed for a PMG5. To reach those pain in the butt screws deep in the case, try to find a magnetized screw tip. Before I had mine though, I used to dip my screwdriver tip in Elmers washable School paste glue LOL - yanno that paste that comes in a lipstick or chapstick style container with the crank base. It worked great at adhering the screws to the screwdriver and would leave no discernable residue. Ghetto fix I know, but hey, it works. There is no shame in taking your time. There are plenty of videos on YT about cleaning and reapplying thermal paste to CPUs but once you've done it, it's a pretty easy and straight forward affair. Less is more with paste. Anyhow, good luck and Im glad your G5 is running again.

 

[Lud DiLettante]

"PART 2"
I guess I had it coming eventually... Yes, I had been going on the one processor and ironically I was at last going to buy thermal paste this week but today the G5 didn't start... (yeah I could offer excuses for the delay....)
I may start another thread as this one is "resolved" but now I'm still reading this old thread, plus various guides, refreshing my memory on how to proceed.
Anyway, the problem is similar to the last time as indicated by the subject line. One thing may be different, as it seems I didn't notice the white power led flashing last time, but this time it does. (No red lights go on anywhere except one flash at power button when I start.)
I suppose I'll go thru reseating video card, verifying speaker cable and resetting logic board before going to the cleaning/thermal paste stage. I'm under the impression that thermal paste could wake up a processor from the "dead"..? Or if it's only a preventive thing then I guess it would be time to get new processor(s) or a new computer...
Anyway I'm still going thru the old stuff/guides. I'll be back...

 

[MagicBoy]

1) As I asked twice back in December ... How many flashes of the Power LED? It's a code to help troubleshoot the fault.
2) Thermal paste WILL NOT "wake a processor from the dead". If you've fried it, then it ain't coming back.

I'm holding out much hope you're listening this time either!

 

[z970]

Augh...

Just replace both processors and call it a day!

 

[Lud DiLettante]

Three flashes... OK I'm prepared... Only tried resetting logic board so far because I realized I wasn't sure about the details of removing/reseating the video card so wanted to check a guide... which I did and see now it's easy.
Anyway, it's consoling to see how inexpensive the used processors are... (but one wonders about their condition...)

 

[MagicBoy]

3 flashes is RAM related IIRC.

 

[Lud DiLettante]

Whoa, that sounds somewhat relieving... but then I think I read about somebody with 3 flashes and it turned out to be the logic board... but then also just the battery in some cases.
It's strange that the G5 guide says nothing about the flash code. What's more, it says nothing about the RAM under "Power-on LED illuminates when power button is pressed and fans spin continuously but there is no boot tone or video" which is what I have. Although Eyoungren also mentioned RAM at the beginning of this thread.
Guess I won't try the video card next, then, but go through the RAM sticks.
(This has been slow progress for me because I don't have other net access at home except the Iphone and I hate to look for large amounts of info or type posts on forums with it, so I use a library computer.)

PS. Started wondering about the battery, as I've never replaced it... how many years are they supposed to last, anyway..?

 

[MagicBoy]

Bad memory slots was a reasonably common type of failure on some early G5s. The error code is reporting the symptom not the definitive cause.

Might help if we knew what precise model it is.

 

[0248294]

RAM related issues can stem from issues with the memory controller. On some models of the PowerMac G5, the board flexes due to the constant exposure to heat during use, which can cause connection issues with said chip. That can, in term, cause the Mac to report RAM issues, while the memory controller is actually at fault. All the Mac knows is that the RAM has failed the memory testing, but of course a faulty memory controller will cause the Mac to "think" this is the issue. It could still be RAM related, of course, but a memory controller failure isn't unheard of.

Basically, if the battery replacement, and RAM shuffling, along with any other tests/fixes you can come up with, do not solve your issues, consider the G5, or at least its logic board, a lost cause. "Baking" the logic board could have the potential of temporarily bringing the board back, but like the RROD on Xbox 360s, they all fail for good at some point. I really hope this isn't the case for you, though.

 

[Lud DiLettante]

The model is the dual 1,8 GHz as confirmed by Chibiterasu earlier in the thread, I still *think* it's the original one but maybe it could be the 2004 one.
(By the way Magicboy, I still haven't found your december questions about the number of flashes, just one about flashing in general, which I answered... )
Yep I haven't had time to proceed, but I guess I'll start with shuffling the RAM..? Apparently getting a new battery is one thing... And despite 3 flashes, should I still go thru the G5 troublehooting guide steps of reseating video card/reseating processor..?

 

[z970]

The model is the dual 1,8 GHz as confirmed by Chibiterasu earlier in the thread, I still *think* it's the original one but maybe it could be the 2004 one.
(By the way Magicboy, I still haven't found your december questions about the number of flashes, just one about flashing in general, which I answered... )
Yep I haven't had time to proceed, but I guess I'll start with shuffling the RAM..? Apparently getting a new battery is one thing... And despite 3 flashes, should I still go thru the G5 troublehooting guide steps of reseating video card/reseating processor..?

If the processors look like this:

It's the 2003 model.

If they look like this:

Then it's from the 2004 line.

Thank you, come again.

 

[Lud DiLettante]

Yep it's the earlier, thanks!

 

[0248294]

Yep I haven't had time to proceed, but I guess I'll start with shuffling the RAM..? Apparently getting a new battery is one thing... And despite 3 flashes, should I still go thru the G5 troublehooting guide steps of reseating video card/reseating processor..?

Yes, you should try all of those things to narrow down the problem.
Also, check out this thread, specifically the first post: https://68kmla.org/forums/index.php?/topic/21496-power-mac-g5-three-led-flashes-with-good-ram/
The OP discusses the issue with the memory controller I mentioned before, and also shows a few temporary fixes that he applied. You could try the same things to see if it allows you to get at least further than a black screen and no chime. But again, this will basically mark the G5('s logic board) as a lost cause.

 

[z970]

Yep it's the earlier, thanks!

Glad to be of service.

 

[Lud DiLettante]

OK, I reseated the video card & started removing RAM in pairs, but with the G5 not booting I sorta lost hope before getting to shuffling individual sticks... However I started a new thread at last: https://forums.macrumors.com/thread...-flashes-troubleshooting-last-stages.2076147/
So maybe we could continue there...
If anybody new reads this later: the *original* problem was resolved at the end of the first page.