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eVasilis

macrumors 6502
Original poster
Jan 13, 2010
429
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Hi all,

Very recently my 5,1 has been refusing to boot. When it does, it does so after numerous attempts, i.e. pressing the power button, no chime, me waiting in front of a black screen and, then, after a while pressing the power button to shut it down because nothing happens. This could be repeated too many times and sometimes the only way for it to boot is to press the button next to the cmos battery, connect everything back and press the power button. So far I have reset nvram and smc, repleced the cmos battery and reflashed the boot rom chip with a reconstructed rom. I did run ASD an I found out that the PCI boost A line is dead. Initially I thought this behaviour was due to the GPU drawing too much power during start up but it does the same with the original gtx 120 which is only pcie powered, booting from a vanilla Mojave disk.

When it behaves the way it does all fans work properly so maybe it is not the psu (is it?). Ideas anyone?

Some in info:

MacOs 12.7.4 via opencore booting from nvme ssd, radeon RX 5700, reference model, usb3 pcie card

Thanks
 
Try a replacement backplane?
I feared that was the only option... I never did something like that before but there is always a first time! I am in the market for a new computer but they way apple approaches their hardware I fear I will end up with a mac that cost me a lot but sooner rather than later no longer supported.
 
I feared that was the only option... I never did something like that before but there is always a first time! I am in the market for a new computer but they way apple approaches their hardware I fear I will end up with a mac that cost me a lot but sooner rather than later no longer supported.
Just get a 7,1 like everyone else is doing at the moment from the ipowerresale firm. 16 core xeon, probably 96GB ram and 2TB SSD,W5500X as a starting point and pretty cheap.

There were even brand new machines available.

If you wanted a traditional upgradable machine the above is it. And you can run latest macOS Sonoma without needing hacks or workarounds.

You could even get the Belkin power cable kit and put your RX5700 in as a second GPU.
 
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Just get a 7,1 like everyone else is doing at the moment from the ipowerresale firm. 16 core xeon, probably 96GB ram and 2TB SSD,W5500X as a starting point and pretty cheap.

There were even brand new machines available.

If you wanted a traditional upgradable machine the above is it. And you can run latest macOS Sonoma without needing hacks or workarounds.

You could even get the Belkin power cable kit and put your RX5700 in as a second GPU.

Problem is they are 5 years old and soon the latest OS will not operate on them. Worse is that software companies now upgrade things which require a recent OS.

But yeh ... I was considering one ... but for me, they'd cost around the same as faster Apple Silicon alternatives. And with them I'd have a longer period B4 replacement. Except of course for the Windows option.

The best thing about a 7,1 IMO is that it would be a painless way to switch to Windoze.
 
Has anyone really said exactly with total certainty what MacOS will be the last one to support these machines or is it just speculation?

As far as I've seen it's just speculation with no base. People saying 14, 15...
 
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Has anyone really said exactly with total certainty what MacOS will be the last one to support these machines or is it just speculation?

As far as I've seen it's just speculation with no base. People saying 14, 15...

No. And I reckon you know that!

We can only guess. But because it's the last intel machine, there seems little incentive for Apple to keep things going. The 5,1 could be kept going because Apple kept producing Intel machines.

It'll be two steps: last software then after a few more years the security upgrades will stop.

Some say up to 5 years for the security upgrades to continue.

For users who are not worried about security and do not need to change their software versions, it's worth thinking about. And it would be a reliable Windows computer.

I think its main benefit is easy upgradeability (although GPU limited) and for some it can handle lots of RAM. As far as speed goes, for most users it will be a lot slower than Apple Silicon, which will continue to get faster and faster. But for me 5 years is not long ago, and back then the 7,1 seemed the answer to all our prayers. For myself I could bung in my Highpoint RAID card which would save me worrying about what to do with it with Apple Silicon. And Apple RAM prices and disk prices annoy me a lot. I reckon though in 5 years the 7,1 will be worthless for most Apple users. Nice piece of art and manufacturing skill though. Except for lots of intel workstations out there.
 
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OK - so maybe 2.5 years .. what do you reckon? You would know.

If I had to bet, macOS 15 is the last one supporting Intel, 5 years after the last Mac with Intel was released. So, 2019 Mac Pro and any other 2020 Macs with Intel will have Security Updates until September/October 2026.

How threatening are the security issues when Apple stops providing them?

Even if you do not connect to the Internet, once Apple removes Security Update support, apps stop supporting it. BigSur is not supported for current Adobe apps/ProTools and etc.

This is the real issue.
 
If I had to bet, macOS 15 is the last one supporting Intel, 5 years after the last Mac with Intel was released. So, 2019 Mac Pro and any other 2020 Macs with Intel will have Security Updates until September/October 2026.



Even if you do not connect to the Internet, once Apple removes Security Update support, apps stop supporting it. BigSur is not supported for current Adobe apps/ProTools and etc.

This is the real issue.

OK.

Ironic that the Classic Macs will last as long as the 7,1 due to both loosing their security updates at the same time.

Real restraint of trade stuff, but then, the big software companies are cleverer than many governments it seems to me.
 
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OK.

Ironic that the Classic Macs will last as long as the 7,1 due to both loosing their security updates at the same time.

Real restraint of trade stuff, but then, the big software companies are cleverer than many governments it seems to me.
A possible reason why developers drop support for out of support operating systems is due to Apple's development tools dropping support for them. If a developer wants to code for new features in the latest OS they'll have to upgrade their development tools which could potentially mean losing support for out of support operating systems.
 
A possible reason why developers drop support for out of support operating systems is due to Apple's development tools dropping support for them. If a developer wants to code for new features in the latest OS they'll have to upgrade their development tools which could potentially mean losing support for out of support operating systems.

Not the real reason since there are workarounds for that, like having dedicated Macs to build for prior releases and other tricks, there are several developers that still do it.

The real reason is the cost of maintaining support/complexity versus the return - after a certain point is just not economically viable to do so for some minor number of users.
 
Not the real reason since there are workarounds for that, like having dedicated Macs to build for prior releases and other tricks, there are several developers that still do it.

The real reason is the cost of maintaining support/complexity versus the return - after a certain point is just not economically viable to do so for some minor number of users.
Yes, that's possible. I didn't feel the need to state something that was obvious. Apparently I was wrong.
 
I did run ASD and the only tests it failed were the pcie boosta sensor reading, being below low point, well it is dead, and the linkwidth test for pcie slot 1, not being 16X. The latter does not worry me as it is probably due to the fact that I ran asd using a gt 120 whic reports in my system as being 8X. What puzzles me is that after I disconnected the gpu's cables from the logic board, it is an rx 5700, and connected then to am external PSU, the macpro keeps behaving the same way, when pushed a little freezes and then shuts down. Rebooting is also an adventure as it my take several hard reboots to get to the desktop and some times when the desktop appears it shuts down again! Oh well, I'm out for a backplane replacement so if you know of any reputable sellers in Europe, please let me know! What is strange is that the issues are present with the gt 120 too.

PS Could somebody please explain to me why I get this behaviour even with an external psu powering up the gpu?

Thanks!
 
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[QUOTE="eVasilis, post: 33131174, member: 398613"

Northbridge problems?

Probably. Most of the cases are caused by the northbrige heatsink push-pins being broken, but could be also caused by other, unrelated to heatsink, CPU tray problems.
[/QUOTE]

So I should be after a backplane and CPU tray...
 
And this is the latest error message from the latest KP:

p_kdp_enter() NMI pending on cpus: 0 1 2 3 4 5 6 7 8 9 10 12 13 14 15 16 17 18 19 20 21 22 23

Northbridge problems?

Probably. Most of the cases are caused by the northbrige heatsink push-pins being broken, but could be also caused by other, unrelated to heatsink, CPU tray problems.

I'd start testing a CPU tray if available, if not, then verify the northbridge heatsink push-pins.

So I should be after a backplane and CPU tray...

I'd start inspecting the northbrige push-pin, before buying anything.

Btw, it will probably be cheaper to buy a working barebones Mac Pro than each part separately.
 
And this is the latest error message from the latest KP:

p_kdp_enter() NMI pending on cpus: 0 1 2 3 4 5 6 7 8 9 10 12 13 14 15 16 17 18 19 20 21 22 23

Northbridge problems?
This can also be a dead CPU as well. I had similar on my dual CPU 5,1:


In my case Northbridge was fine (and all temps were low, even the Northbridge) but I had a faulty CPU. Once I determined which CPU was faulty and replaced it then the machine ran perfectly again.

Summary: Faulty CPU, verified normal temps, replaced faulty CPU, works fine.

Once you have checked Northbridge and temps, check the CPUs.
 
This can also be a dead CPU as well. I had similar on my dual CPU 5,1:


In my case Northbridge was fine (and all temps were low, even the Northbridge) but I had a faulty CPU. Once I determined which CPU was faulty and replaced it then the machine ran perfectly again.

Summary: Faulty CPU, verified normal temps, replaced faulty CPU, works fine.

Once you have checked Northbridge and temps, check the CPUs.
How did you determine which cpu was at fault? Because in system info both show to be working. Also when I ran ASD there were no problems reported with the CPUs.

Thanks!
 
How did you determine which cpu was at fault? Because in system info both show to be working. Also when I ran ASD there were no problems reported with the CPUs.
I just pulled them out. I got lucky that the first one I replaced was the problem one.

I knew the Northbridge was fine because I fixed that up with new thermal paste and new spring clips and also had supplementary fan cooling for it which kept it down to 55ºC even though it's a dual CPU machine.
 
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