MacBook Pro is slow... but works fine on bootcamp!

[CharleyNapalm]

Hey folks, just looking for some help here!

I have an early 2011 MBP, 512GB SSD, 16go RAM. I replaced the battery a couple months ago and the MacBook is now very slow when on MacOS Sierra. When I run Windows 7 on Bootcamp, the computer works perfectly fine just like if it was brand new.

On MacOS Sierra, it is just impossible to do a simple task. Whenever I press a letter on the keyboard, it takes 5-10 seconds to appear on the screen. When I move the mouse around, it looks like a 2 FPS old video game.

Another weird thing, sometimes I'm able to be on MacOS Sierra for 2 hours and everything works just fine. At some point for no apparent reason, everything becomes very laggy. On bootcamp, it is always 100% stable.

I tried so far:
- Reset PRAM
- Reset SMC
- Reinstall MacOS Sierra from scratch
- Reinstall El Captain from scratch

No success so far. Wondering why Windows 7 is working perfectly but having so much trouble with the mac portion...

Thank you for your help.

Charles

 

[cbautis2]

Planned Obsolescence for sure

 

[Sanpete]

What other software are you running?

 

[Altis]

Sounds strange. What SSD are you using? I'm wondering if that's the source of the issue since OSX can be quite particular about SSD drives, whereas Windows hardware support is far more extensive.

If you have a spare drive around, try popping it in and doing a fresh install of El Capitan.

Also keep in mind that OSX/MacOS tends to be quite laggy for a while after an install while it indexes.

I have a 2010 MBP and El Capitan runs alright on it (not great, though). Sierra runs poorly.

However, Linux and Windows 7/10 run absolutely beautifully on it. I'll likely just use those when El Capitan support drops, unless Apple decides to bring back the 17".

 

[New_Mac_Smell]

Does sound a bit strange, however Sierra came out 2016, Windows 7 was 2009. Could indicate why a 2011 machine would prefer the latter.

As @Atlis suggested, try an older version of OSX. Sierra is compatible but you're right on the limit unfortunately.