Need help with reviving MBP 15" 2011 with dGPU and now a slowdown issue

[Codpeace]

Hi everyone. I could REALLY use some help.

I have a late-2011 15" MBP with a discrete GPU. It suffered the famous glitch in that model where the GPU failed and progressively I couldn't boot the machine. Eventually, it bricked (apparently permanently) in 2017 and I had to buy a new machine.

Recently I learned of a way to bypass the dGPU so the machine could boot and operate using the integrated Intel graphics (if interested, see http://dosdude1.com/gpudisable/). I managed to get the machine to boot for the first time in 4 years! But the battery is utterly shot, unsurprisingly.

Meanwhile, while I could get the machine to boot into High Sierra, it took forever to boot and then operated so slowly that it is pretty much unusable. Something is desperately wrong. Just moving the cursor across the screen, it stutters and jerks and lags. Opening Finder takes ~45 seconds. Obviously, the CPU is grinding through some kind of task repetitively (which is not apparent from Activity Monitor) or else is throttled by some 90%+. I've tried to run Sierra with the same result. I can't seem to download any earlier operating systems to try those, but this machine has a 2.4g i7 and shouldn't have a problem with either of Sierra or High Sierra.

Is the fact that the battery is dead a possible source of the problem? Or is there a possibility that, while it's bypassed, the dGPU is still operating super hot and the machine throttles for heat? (The fans aren't running, through). I tried to understand this page (https://apple.stackexchange.com/questions/267581/gpu-problem-boot-hangs-on-grey-screen/295805#295805) but it went over my head.

Please, can anyone help me here? It is very vexing. I can't understand what would be causing the machine to operate so slowly...

THANK YOU!

 

[MBAir2010]

can you use a power chord?
i know this sounds belittling, but can you?
i hope we reset the pram and ran a systems disc check
an your problem solved before i post my rambling:

i fixed someones MacBook air running lion in 2015 and that was sloooooow
so i shut down, restarted and reset everything
the updated, shut down restarted and the macbook air ran great
(not pertaining to your situation)
but smelled like devils lake red lager so we uncased everything swabbed everything and replaced everything
and that worked!
my iMac g4 ran grey streak on booting gup
i gave that away thinking graphics card
nope- a new battery inside was dead
that is in costa rica performing photoshop graphic for a design company

the theme to the is never give up or think one thing is wrong
keep on trying, these macs are like cats!

 

[Codpeace]

can you use a power chord?
i know this sounds belittling, but can you?
i hope we reset the pram and ran a systems disc check
an your problem solved before i post my rambling:

i fixed someones MacBook air running lion in 2015 and that was sloooooow
so i shut down, restarted and reset everything
the updated, shut down restarted and the macbook air ran great
(not pertaining to your situation)
but smelled like devils lake red lager so we uncased everything swabbed everything and replaced everything
and that worked!
my iMac g4 ran grey streak on booting gup
i gave that away thinking graphics card
nope- a new battery inside was dead
that is in costa rica performing photoshop graphic for a design company

the theme to the is never give up or think one thing is wrong
keep on trying, these macs are like cats!

Yes, I've been running it only on the power cord -- because, after all, the battery is DOA. It won't hold a charge at all. I can get a cheap replacement battery for, like, $30, so I would do that but would rather not if that's not the problem. I would only run this machine on AC power as a file/media server; no need for that battery unless it needs one to operate properly.

I ran the PRAM/NVRAM reset but the dGPU disable requires a NVRAM mod so I can't run that again after that change is effected. I also ran an SMC reset prior to the dGPU disable procedure.

Thank you for your thoughts! No need to worry about belittling here -- this is such a vexing problem it seems like I might be making some kind of obvious mistake. But I don't think I am...

 

[Codpeace]

EDITED: sadly, it seems I spoke too soon... 😞

~~~~~

So! After 4 days of struggling with this, MANY hours into it, it seems to have resolved itself.

I got Sierra to boot. Then I installed iStat Menus to get more insight into what processes were running: “kernel_task” was cruising at 600-750% constantly. That looked like MacOS interior maintenance so I left it alone for an hour or two ... and now everything seems good!

So, crossing fingers, I might have brought my old, really good friend back to life... I sure hope so.

Totally figures, right? As soon as I send out a prayer for help things just sort of magically ... heal. NOT COMPLAINING.

Thanks for reading and considering helping. This place is the best.

 

[profcutter]

Dead battery means CPU runs at 50%. That’s going to be an ongoing problem.

 

[Codpeace]

Dead battery means CPU runs at 50%. That’s going to be an ongoing problem.

Thank you. Could you please explain a little more? Why is this true? Would a new battery help it operate even on AC power...?

 

[profcutter]

Yeah, I can’t tell you why they made that decision, probably a concern that if the CPU is running full tilt, the power adaptor may not be able to provide enough power for momentary spikes, the battery then provides a buffer of additional power. So the CPU runs in limp mode to prevent sudden shutdown. That‘s a guess, but I think it’s pretty sound logic. I had a 17 inch, and it ran so slowly it was completely unusable. A new battery got it going back at a reasonable speed. If you search the forums, you’ll see it’s a common problem, and yes, it will run at full speed on AC with a functioning battery, otherwise you’re stuck at 50% as soon as the system realizes there’s no battery backup.

 

[Codpeace]

Yes, it’s def logically sound, which was why I wondered if it might be part of the problem. I can live with that. I just plugged in a USB drive to clone all the **** that seems to operate the machine (!) so I don’t lose my work — and “kernel_task” is back at 700%+. At least now I know what’s up. (Is it indexing...?)

EDIT: So it seems to be more or less permanently back at 700%. What in the world is it doing? I researched a bit and it seems macOS is engaged in a lot of throttling. But throttling of what? And why? Is this, again, because of the DOA battery...? There is def no heat problem. The fans aren’t engaging at all.

 

[profcutter]

Yeah, it’s not heat, it’s available power. I don’t know if you have other problems compounding the issue, but in most cases, it’s cleared by a new battery. If it’s indexing, it will take forever if it’s throttled.

 

[Codpeace]

Yeah, it’s not heat, it’s available power. I don’t know if you have other problems compounding the issue, but in most cases, it’s cleared by a new battery. If it’s indexing, it will take forever if it’s throttled.

Cool. I'll just buy a new generic battery and install that.

Really appreciate your assistance, @profcutter ! Hopefully it works lol...

 

[MBAir2010]

these intel MacBooks are tough and can run forever under the proper adjustments and care.
too many other MacBook owners give up too soon on them!
I'm happy things are working on yours!

 

[Fishrrman]

OP:
If you're going to open the back to put a new battery in, have you considered buying a cheap SSD to put in there, too?
Nothing fancy, the cheapest one you could find would probably do...

 

[profcutter]

I second this proposal. An SSD will make the computer seem like new.

 

[Amethyst1]

these intel MacBooks are tough and can run forever under the proper adjustments and care.

Those GPU problems are annoying as heck though.

 

[Codpeace]

OP:
If you're going to open the back to put a new battery in, have you considered buying a cheap SSD to put in there, too?
Nothing fancy, the cheapest one you could find would probably do...

I've done all kinds of things to that computer -- RAM swaps, new drives, yanked the CD and installed a second drive. It's a really fun computer for minor tinkering, easy to access, to clean, and well laid out to get to the stuff an amateur likes to fiddle with.

Anyway, I had an SSD in it for a long time before it bricked, an OWC Mercury Electra 6G 500gb. So I reformatted it and installed a fresh copy of High Sierra and that is what simply wouldn't work. It's still acting intransigent, with "kernel_task" going nuts. I'll pick up a new battery and see how things work and report back.

 

[Codpeace]

Those GPU problems are annoying as heck though.

You just can't imagine the trauma it put me through... I've tried to come up with an analogy and the best I can do is: it's like if you've ever had something stolen. You KNOW where you put it. It's not there. It's not possible it's not there. You look everywhere, even though you know where it is. You keep checking. Eventually, it dawns on you that it must have been stolen... And it's so incredibly hard to accept.

It was just like that with this otherwise awesome computer. This series of baffling weirdnesses kept happening. And progressively severely. Then it had a fiddly boot. Then it mostly wouldn't boot. Then it wouldn't boot ever. But it had been such an excellent and reliable friend and tool! Maybe a better analogy is like when a dog gets cancer and over time just ceases to be the dog it was, and eventually ceases to be a dog at all. And then you have to say goodbye, but never quite believe it's true.

I was very upset. That's why I'm putting such effort into reviving it. It's irrational but it was my first Apple computer and it's kind of emotional for me. 🤷‍♂️