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antijoey
02-06-2007, 08:23 AM
power mac g5 dual 1.8, 256M ram, 120G hd, osx 10.3.9

problem began when g5 refused to wake up. forced shutdown. when booted, i get the startup chime, hd spins, fans start, then nothing. black screen.

after 30-40 seconds, fans begin coming on, becoming louder until i press the power button.

pram will not reset. will not boot into safe, will not boot into open firmware, will not boot to cd.

reset pmu. same problem.

this machine is about 4 years old and has performed flawlessly until now. there have been no recent s/w installations except normal security updates. any clues?

aj

Sherman Homan
02-06-2007, 08:41 AM
The G5 dualies have major league issues with ram chips. I am curious though, do you really only have 256 megs in there?

antijoey
02-06-2007, 09:07 AM
actually, no. should have 256M X2 (equalling 512M). thanks for correction!

aj

Sherman Homan
02-06-2007, 09:14 AM
Any way to swap out those chips and pop in another set? Those machines are notoriously picky about ram.

antijoey
02-06-2007, 10:45 AM
sadly, the only pc3200 184pin ddr sdram in the house is in this computer. my understanding is that this ram has a lifetime warranty from apple. is it worth it to give them a ring?

aj

marchutch
02-06-2007, 10:48 AM
Any way to swap out those chips and pop in another set? Those machines are notoriously picky about ram.

I will second this my dual 2.0GHz G5 exhibited the same behaviour when I tried to put some cheap RAM in it. Start up chime, black screen with fans ramping up to maximum speed. Sounded like a freight train going past my house. Only way to fix it was to go back to original RAM configuration.

So maybe your RAM has in fact gone south.

JDV
02-06-2007, 11:06 AM
Maybe. But be prepared for them to have you go through a lot of procedures that you may already have done. They probably won't simply replace them without a rather long song and dance, I fear.

RAM is comparatively cheap these days, and 512 MB for a G5 is sort of meager in any case. You might be better off considering buying a couple of other sets of DIMMS from a reputable vendor to take it to 1 GB. You could, I think, buy two more 256 MB DIMMS and simply replace the existing memory with the new memory. If that solves the problem, you know you have bad memory chips. If it doesn't, you'll have additional memory to add to the machine when another cause for the problem shows up. If it DOES fix the problem, you'll have a very strong case to have Apple replace the set with the lifetime warranty.

Joe VanZandt

antijoey
02-06-2007, 11:18 AM
i think i'll first jump through hoops for apple. this is the ram that shipped with the machine, so i will first assume that it is still warrantied.

yes, ram is pretty cheap these days; but then again, so am i! hahaha

will post results later today!

thanks!
aj

marchutch
02-06-2007, 12:06 PM
i think i'll first jump through hoops for apple. this is the ram that shipped with the machine, so i will first assume that it is still warrantied.

yes, ram is pretty cheap these days; but then again, so am i! hahaha

will post results later today!

thanks!
aj


I got two pairs of 512 MB RAM chips of this type of ebay for 30 a pair. This equates to $60 (US). Do you perhaps have some Scottish ancestors? lol. kidding dude.

And before any admins get the hump.... I am myself a Scot by blood and birth.

antijoey
02-06-2007, 12:24 PM
Do you perhaps have some Scottish ancestors? lol. kidding dude.

actually, i believe so!

marchutch
02-06-2007, 02:04 PM
actually, i believe so!

well, all the better! :-)

antijoey
02-07-2007, 12:22 PM
apple is completely unhelpful. seems there must be a service agreement before honoring a "life-time warranty" on their RAM.

anyway, it has been suggested (on another forum) that this could be a power supply issue. any info out there on power supply specs for this model? should be easy to rule out after a bit of measurement...

also, where can i find motherboard led diagnostic info? throughout this problem, i get solid red at led labeled R58 / 1229 and no others.

thanks all!

the antijoey

bramley
02-07-2007, 12:49 PM
also, where can i find motherboard led diagnostic info? throughout this problem, i get solid red at led labeled R58 / 1229 and no others.
You may want to check out this (http://docs.info.apple.com/article.html?artnum=302527) Apple doc (I realise that the top half of the document won't apply to your machine but the item concerning powerlight LED should.)

antijoey
03-09-2007, 07:23 AM
was finally able to afford a diagnosis.

the video card has failed. need to replace. still no word, though on how to reach that conclusion.

could have been worse, i suppose. any advice out there on a suitable replacement other than apple's $280 one?

thanks for all the replies.

aj

trevor
03-09-2007, 08:41 AM
Some video cards for sale (http://eshop.macsales.com/shop/video/hardware/)

Trevor

vanyie
06-06-2007, 08:18 AM
power mac g5 dual 1.8, 256M ram, 120G hd, osx 10.3.9

problem began when g5 refused to wake up. forced shutdown. when booted, i get the startup chime, hd spins, fans start, then nothing. black screen.

after 30-40 seconds, fans begin coming on, becoming louder until i press the power button.

pram will not reset. will not boot into safe, will not boot into open firmware, will not boot to cd.

reset pmu. same problem.

this machine is about 4 years old and has performed flawlessly until now. there have been no recent s/w installations except normal security updates. any clues?

aj

HI, i'm not sure it's correct to append on another thread, but i have the same problem that antijoey.
I have a Powermac late 2005 with 256mbx2 ram and other 512mbx2 ram kingston.
The powermac has worked many months without problem, has not connected to internet, it's protected by a ups. I have done everithing as antijoey excet boot into safe and boot into open firmware.
I have tried to change ram and slot, to boot with/without videocard, with/without ram, with/without hd, and obtain always the same answer.
I suppose could be video card or logic board (motherboard).
I have read the doc on diagnostic leds and i have no light leds (except led 7 during startup as should be)
Before i call apple assistance have you any suggestion?

Can i use a "normal" (not for mac) video card pci express to see if there's life??

Thanks in advance
Vanyie

trevor
06-06-2007, 08:59 AM
Can i use a "normal" (not for mac) video card pci express to see if there's life??

You can't use a video card with Windows firmware on a Mac. You need to use a video card with Mac firmware.

Trevor

vanyie
06-06-2007, 10:10 AM
You can't use a video card with Windows firmware on a Mac. You need to use a video card with Mac firmware.

Trevor

OK, thanks
:(

vanyie
06-06-2007, 10:20 AM
You can't use a video card with Windows firmware on a Mac. You need to use a video card with Mac firmware.

Trevor

Sorry, another question perhasps a little bit OT:

I didn't want use a pc-videocard with macosx but only to see the first boot screen or the screen of "Apple Hardware Test" booting... because at this time i see only a "no signal"...
There is an hardware incompatibility or an incompatibility with macosx? I'm only curious...
Sorry if you have to repeat the same answer :o
Vanyie

trevor
06-06-2007, 03:43 PM
The firmware of a Windows video card is incompatible with OS X. The hardware is often identical (although sometimes the flash memory on a Mac card is larger), and there are places that can help you with reflashing firmware. For example, check out the Strange Dogs (http://strangedogs.proboards40.com/index.cgi) forum.

Trevor

vidar
11-02-2007, 09:43 AM
No keyboard commands worked... no video, normal lights&beep.

So:
Did a part of the procedure for flashing firmware:

with machine off, press&hold the powerbutton until tone is heard.

When I did this the monitor woke up and i was in nvram-mode...

(i think it reflashed last firmware & did a reset of ...?)

Typed mac-boot (it says how to start normal boot)

Voila!! all well from then on! :-)

Vidar

MoSo
11-26-2007, 06:54 PM
Not to hijack this thread, but I have exactly the same problem with my G5.

I press the power button, it beeps, but the screen remains blank. Slowly the fan revs up and in the end it sounds like an express train going through the room. But, no contact with the computer.

I have tried booting holding the ctrl + optio n+ O + F (and all other key combos) to get into the open firmware, but it doesn't respond to at all.

But here is the catch Occasionally, I can get it started. About one-in-ten times, it brings up open firmware, and I can do a "reset-nvram" and "reset-all" and it just boots and everything is fine. Literally perfect. I just can't shut the machine down.

So, I don't believe it has anything to do with failed RAM or graphics cards. It may be some check during the start-up process, but once it gets past that the problem is gone.

I think what triggered it was that I installed a new logitech keyboard with a driver that conflicted with the old one. But that may just be a random coincidence.

Any help would be great.

Las_Vegas
11-26-2007, 10:19 PM
Replace your PRAM Battery. You'll find it on the logic board inside. It's available at Radio Shack for around $12US, among many other sources. Just get the most recent date on the battery you can find.

iPodista
12-20-2007, 02:37 PM
just read this to cure the new ram - wont boot ..black screen... fans blowin' a hooly syndrome.... the posts did not help me however i fixed the problem..this is how for anyone like me who stumbles here willing to give anything a go...

I had 2 x 512mb ram chips and bought 2x1gb chips hopefully to add. Opened G5 2ghz Dual ( dual layer dvd) which has 4 memory slots in 2 pairs... the ram chips were not in a paired slot but placed one in each pair. to tidy up i moved the 2x512 into one pair and put the 2x1gb together as the sales blurb mentioned they had to be purchased paired into the other pair of slots...

after a bit of pissing about i eventually pairing a 1x512 and 1x1gb into each pair of slots and the mac restarted and the fan sounds died... it maybe a cheap ram thing for some of you but on getting the black screen and the winds of Tarifa when you start up try spread your memory chips across the paired ram slots rather than group together

Steve46
12-26-2007, 10:58 PM
I had basically the same problem as the original poster, AntiJoey, and MoSo, above. That is... PPC G5 power on, lights, hdd, normal fan noise... blank screen only... fan gradually speeds up to hurricane force... no ability to interact with the mac whatsoever.

This happened to me after I had upgraded/added new ram. The solution for me came when I realized that I had the ram in the wrong slots. G5 memory needs to be in matched pairs and the key is that the TOP of memory bank 1 is matched to the BOTTOM of memory bank 2 and vice-versa. D'oh!

Not sure if it matters, but for completeness sake, I also reset the SMU on the planar board by pressing the button after re-situating the memory in the correct slots.

nastrology
01-16-2008, 06:49 AM
power mac g5 1.6, 768M ram, 80G hd, osx 10.5

problem began when I tried to install new Ram, power came on but no chime, Fan also comes on, then a flashing led above the power button.

I tried reseting the pram no luck there

Then I tried to reset smu, but now the power led takes a few seconds to come on then it goes off for about 8 secs then comes back on again continously doing this and nothing happens.

this machine like others i can see on here is about 4 years old and has performed flawlessly until now. the only major change has been updateing to leopard but that was working fine also.

Please can someone help me out with this.

Thanks
Nas

lbeachmike
02-15-2009, 10:11 PM
Thanks Steve46!

Wow - this information saved me so much trouble! Nobody at Apple support could identify the fact that our problem was the mismatched pairs - it was entirely non-obvious that the top of memory bank 1 is paired with the bottom of memory bank 2 and this is the only place we found that information.

In looking back at Apple's docs, it is actually there, but entirely vague. From the board itself, it's non-obvious. And in the way Apple reports the memory, it does not correlate to the slots where the memory is installed.

It looks like lots of people have run into this issue.

Thanks so much!

charizard
04-18-2011, 02:01 PM
Need help. I have replaced the PRAM battery a month ago when I experienced this problem. I is now happening again. The battery is dated Nov 2010, so it is fairly fresh. Does anyone think I need another battery? or is there another issue I am overlooking.