MP 1,1-5,1 Help! Mac Pro 4,1 (5,1) won’t boot

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
Hi everyone

I recently acquired an untouched Mac Pro 4,1 running Snow Leopard.

Did everything required to update to Mojave including all firmware flashes (Netkas & macOS) and it was running with no problems at all.

This morning, decided to do a CPU upgrade to W3680... no chime, no boot, GPU OK diag LED flashing.

GPU is fine, checked for sure in my old 2,1, also tried the GT120 that came with the 4,1.

Suspected a bad CPU, so decided to put the old W3520 back in.

Same issue. No chime, no boot, flashing GPU OK diag LED

What have I done???

Any help would be great
 

MIKX

macrumors 65816
Dec 16, 2004
1,421
519
Aussie in Japan
richgoga

Any RED LED lights inside the case ? especially on the CPU Tray.

Bolt tension ( CPU heatsink ) is crucial.

Is the cMP a DUAL or Single CPU ? ( make a SIGNATURE in your Macrumors profile. ).
 

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
richgoga

Any RED LED lights inside the case ? especially on the CPU Tray.

Bolt tension ( CPU heatsink ) is crucial.

Is the cMP a DUAL or Single CPU ? ( make a SIGNATURE in your Macrumors profile. ).
Hi, sorry. I’ll add a signature later on...

Single CPU, no red lights.

I’ve tightened the heatsink bolts until they stop, then a slight turn to finish (using hex key with a handle)

Interestingly, just powered on the Mac with no cpu installed an GPU ok light is now solid green. Obviously there’s a red light on the CPU tray now.

Will check socket pins... Hope I haven’t borked it.
 

MIKX

macrumors 65816
Dec 16, 2004
1,421
519
Aussie in Japan
richgoga

Start again and also check your Northbridge heatsink spring-rivets.

Is your CPU lidded or un-lidded ?

As a test you could replace your original CPU just to verify that nothing is actually broken.
 

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
richgoga

Start again and also check your Northbridge heatsink spring-rivets.

Is your CPU lidded or un-lidded ?

As a test you could replace your original CPU just to verify that nothing is actually broken.
Thanks,

Rivets are fine. Still holding the Northbridge heatsink in place.

CPUs are lidded as this is a single cpu system.

Same issue with original CPU.

I’m at a loss.
 

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
Ok... now even stranger.

Removed the mobo battery. GPU OK light is no longer flashing. Just solid green.

Replaced mobo battery, GPU OK light still ok now.

So, no red lights, diag lights are all green. LED above power button is solid white. Fans all running at normal speed.

Just no chime or full boot.
 

MIKX

macrumors 65816
Dec 16, 2004
1,421
519
Aussie in Japan
Have you done a PRAM reset ( 3 consecutive times ) ?

Important : Are you aware that installing LIDDED cpus in 4,1 requires a different technique to compensate for the difference in height between lidded / un-lidded cpus ?

Perhaps you need to read up on the above.

Oh, and also, if you want quick, informed replies to your questions . .please make a SIGNATURE in your Macrumors profile to show your particular mac Pro set up.

My SIG is at the end of this post as an example.
 

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
Have you done a PRAM reset ( 3 consecutive times ) ?

Important : Are you aware that installing LIDDED cpus in 4,1 requires a different technique to compensate for the difference in height between lidded / un-lidded cpus ?

Perhaps you need to read up on the above.

Oh, and also, if you want quick, informed replies to your questions . .please make a SIGNATURE in your Macrumors profile to show your particular mac Pro set up.

My SIG is at the end of this post as an example.
Thanks again for your reply

The single processor 4,1 shipped with LIDDED CPUs. Is the dual processor trays that used deLIDDED ones.

All guides state this and the swap is simple. Or it should have been. https://www.ifixit.com/Guide/2009+Mac+Pro+CPU+upgrade+(single+socket)/100358

The CPU that came out and was working THIS MORNING is lidded.

Put back in... not working.
[doublepost=1566049120][/doublepost]
Thanks again for your reply

The single processor 4,1 shipped with LIDDED CPUs. Is the dual processor trays that used deLIDDED ones.

All guides state this and the swap is simple. Or it should have been. https://www.ifixit.com/Guide/2009+Mac+Pro+CPU+upgrade+(single+socket)/100358

The CPU that came out and was working THIS MORNING is lidded.

Put back in... not working.
Also, I can’t do a PRAM reset if the Mac doesn’t POST or Chime
 

MIKX

macrumors 65816
Dec 16, 2004
1,421
519
Aussie in Japan
OK, how was I to know that your cMP is a single CPU ? Make a sig anyway.

I'm assuming that your 4,1 was disconnected from power during the CPU changeover.

It seems obvious that the cause is something that you did during the process. You need to go back and list step by step everything that you did to point out any mis-steps.

All you can do now is disconnect the 4,1 'til tomorrow and in the meantime, search for similar problems in the Mac Pro threads.

Good Luck.
 

richgoga

macrumors regular
Original poster
Oct 11, 2013
136
56
OK, how was I to know that your cMP is a single CPU ?
snip
Good Luck.
Umm... maybe because it was the first question you asked and the first I answered? :(

Thanks for the the insightful replies.

As for steps taken...
Mac was on, running Mojave
Shut down
Disconnect power cable
Remove processor tray
Remove heatsink
Cleaned old thermal paste
Remove old CPU
Used compressed air to clear dust
Checked Northbridge rivets as I know it’s a common problem.
Install new CPU
Add thermal paste
Reseat heatsink, taking care not to over tighten... stopped when the screws hit the stops.
Plug tray back in
Plug power cable back in
Turned on the Mac
Spent the day troubleshooting to no avail

That’s it. The same thing that several people have done several times.

To clarify what I’ve done to troubleshoot...
I followed the Minimum Configuration guide from here:
http://tim.id.au/laptops/apple/macpro/macpro_early2009.pdf#page32

Everything good (including diag LEDs), all the way to Point 11:
Expected behavior:
• The red-colored error LED on the processor board next to the memory slots at processor A should flash once only as the Mac Pro powers on.
• Startup tone heard (if not, reset PRAM and retest)
• Front and rear processor cage fans (and PCIe fan, if installed) should spin slowly

The led flashes and the fans spin as expected.

There is no chime.

And I can’t reset the PRAM because there is no chime! USB doesn’t work, therefore wired keyboard doesn’t work.

Is it possible to reset PRAM any other way? Internet doesn’t think so.

So, what next?

I know nobody with a 4,1 or 5,1 to test the tray.

Looks like I’m stuck.