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Macbook Pro VERY slow
- Thread starter patseguin
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Good point, no you can't. I just wondered if it hurt my battery leaving it plugged in all the time. I basically used it plugged in as a desktop computer for 90% of the time for the past 8 years.
Just be forewarned that the 15" 2011 MBP has a known dGPU failure flaw. Running in clamshell mode with an external monitor forces use of the dGPU full time. I suspect the reason for your logic board replacement was due to the dGPU failure and is likely to happen again using the dGPU constantly to run the external monitor.
I think your battery naturally reached the end of life. Battery failure can lead to CPU throttling which would explain the slow performance.
I think that you need to keep in mind that there is a battery, and it does need to be "exercised" occasionally - discharged fully and recharged. I do this, with the old MacBook that I usually use in clamshell mode. Disconnect, use as a portable, let the battery discharge. I follow the same tips that I used to follow for a "calibration". Discharge. Shut off, let the system sit unused for an hour or two. Plug in to charger, and let your portable charge fully. Let the battery rest again, 30 minutes or so is what I do. Some info that I see states that you should NEVER allow the battery to go below 30%, or above 80%. I think there is some technical reason for doing that, but I have never tried that. PLUS - I don't know how you could keep the battery under 80% if you are typically using clamshell mode, and have the charger plugged in at all times. Anyway, I don't follow those recommendations. It is almost always plugged in, except for the occasional "exercise" for the battery. Discharge, then recharge fully - 3 or 4 times a year, at the most.
Part of my "discharge" plan is to allow the battery to go to zero, where the laptop goes to sleep. The battery is at zero, so it won't power on again until you plug in the charger.
I will say that discharge completely (to zero) is usually NOT recommended for modern batteries, but I am usually in the middle of that kind of maintenance, so it doesn't stay that way more than a few minutes. I don't ever remember seeing that "never let that go below 3%". I think that is just an arbitrary number, so it doesn't get to absolute "empty" - and, of course, you wouldn't run it on battery alone while in clamshell mode, so you would not likely ever see that 3% when your portable is typically always on the charger.
Part of my "discharge" plan is to allow the battery to go to zero, where the laptop goes to sleep. The battery is at zero, so it won't power on again until you plug in the charger.
I will say that discharge completely (to zero) is usually NOT recommended for modern batteries, but I am usually in the middle of that kind of maintenance, so it doesn't stay that way more than a few minutes. I don't ever remember seeing that "never let that go below 3%". I think that is just an arbitrary number, so it doesn't get to absolute "empty" - and, of course, you wouldn't run it on battery alone while in clamshell mode, so you would not likely ever see that 3% when your portable is typically always on the charger.
The battery was cheap enough. Replace it when it fails again.
@CoastalOR had a good point. The GPU will most likely die long before you need another battery.
Consider a Mac Mini as a replacement (when you need one) since you operate 100% in clamshell mode.
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Yep, that's exactly what I'm going to do when I have the money. Kinda stinks that'll be stuck on High Sierra too, so I'm going to get a Mini asap. Is it much of a step down from this i7 to the i5 in the new mini?
I don't have any idea how the performance will compare. The new Mini i5 is 6 core so the performance may be better than your old i7.
You could always get the upgrade option to an i7 in the Mini but it's more money ($200).
macOS will manage battery life, but I've read you need to discharge and recharge occasionally to maintain battery life, but using off battery all the time obviously chews through the battery life. Deep DOD, (depth of discharge) is what hurts lith-ion batteries most.