MP 1,1-5,1 Attempt to upgrade my 4,1->5,1 to X5672 CPUs - failure #1

[OldMacPro2]

Following the "House of Moth" instructions, I've de-lided two X5672 CPUs.

The method he describes in his Youtube video worked fine for me.

After replacing the stock CPUs in my dual-processor MacPro 4,1 (flashed to 5,1) the system "powers up", fans running, etc, but no boot screen ever appears.

Before I installed the new chips, I noticed one of them was slightly damaged. There was a slight gouge in the top circuit board area, and it left a "hole" where I could see bare metal underneath.

Not sure if I did it, or if it was that way when I received it (they were purchased used off eBay), but that may explain the failure to see the system boot up.

So I assume that if both the CPUs aren't working in a dual-processor Mac Pro, there isn't a built in "failover" that allows it boot off just one?

(Later today, I am going to replace the stock X5550s, just to make sure I didn't do something stupid when I swapped the CPUs out. But I think I was very careful.)

 

[tsialex]

So I assume that if both the CPUs aren't working in a dual-processor Mac Pro, there isn't a built in "failover" that allows it boot off just one?

Install one Xeon to CPU socket B A.

 

[OldMacPro2]

Install one Xeon to CPU socket B A.

View attachment 2099276

Thank you... I swapped the two CPUs and now it's working fine.

These were not "matched" CPUs, but they both have the same specs. Maybe I did a better job installing them the second time?

Whatever it was, working fine now.

 

[OldMacPro2]

My next task is to do the Northbridge heat sink re-paste. I have the new spring clips.

Appreciate all your help, tsialex! You have been a great "Apple Genius" to help me through this.

 

[tsialex]

There are no matched CPUs for the 1366-pins socket, or better yet, all Xeons from a given Nehalem/Westmere retail model are matched.

Back in early 2000s with 603/604-pins and older sockets you needed matching Xeons, since there were more than one S-Spec for a given processor, but it's not the case with Nehalem/Westmere Xeons.