I'm looking at picking up a used 2012 MBP. The price is good, but I'm told it runs really slow and the fans run constantly. I plan on replacing the HDD and maxing out the RAM anyway, but I can't get to the machine to run a hardware test before purchase. Could this be some other sort of hardware issue (logic board)?
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Need help. MBP running hot and slow
- Thread starter luthier42
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The thermal paste might need to be changed if the fan is on constantly.
Is it the 15" model or 13"?
If it has a 5400 RPM HDD and maybe 2 GB of RAM, I could understand why it would be described as slow.
If the fan run constantly, the heat sink could be blocked or thermal paste should be redone.
I recently had a similar issue with my 2011 MBP. You wouldn't believe how dirty it was inside.
I recently had a similar issue with my 2011 MBP. You wouldn't believe how dirty it was inside.
Two possibilities:
Something is running on the machine, maxxing out the CPU, causing it to appear slow to the user and run hot.
Airflow blockage is causing it to run hot enough to throttle, hence appearing slow.
A screenshot of the CPU activity monitor panel sorted with the highest CPU usage at the top will likely tell you, or you can post here, and possibly the vendor can send you before you get it or make a final decision?
Highly unlikely to be the HDD, while they can cause apparent slowness if they are logging errors, that failure doesn't tend to make the machine run hot in my experience.
It won't be the problem unless it is failing, which is unlikely in a 2 year old computer.
The plan is to get a big SSD and max out the RAM. I plan on installing the OS from scratch (you can still do that, right?) so I'm really hoping it's software related. As far as I can tell from research it's either software (resource) related, fan sensor related, or dirt. Does that really cover all the bases or is there some chance that I'm gonna have a bum logic board?
Yes, AHT could catch issues with the logic board.
Do the fans run constantly even with a clean install of OSX?
I'd use the 'issues' presented to drive the price down as far as I could get the seller (and honestly, it should be a KILLER deal, as most Apple owners I know have no idea how to fix anything)
The first thing I'd do, is a full clean and re-paste:
Why would I do these things? Because I've done them before
A temp sensor failing will make the computer default to full blast fans, as it has no idea whether it needs cooling or not and takes no chances.
The sensor itself is about $20 or so if I recall, Apple should fix it for very little money.
If by running hot the guy is just stating that the computer is warm to the touch, well that's just how MBP's are.
I decided against it. After looking at the 38 step repair at iFixit and realizing that I could get the same machine without the heat problem for an additional $70 (a good deal less when you consider the part, thermal paste, and a few tools I don't currently have) and not have to disconnect all those crazy small connections it seemed like it might not be worth the effort and risk that I might damage something in the process. Thanks for all the help guys, I learned a lot.