Hey guys i have a 15" MBP i7 with 4gb ram. Im having some issues whenever i connect to my 27" cinema display. If i leave the lid of the computer open(both screens on) there are no issues, but if i use it with the lid closed, which is the way that i need it to work, it becomes almost unusably slow for certain applications like autocad and iphoto in full screen. I bought the display to use with autocad with my laptop closed to preserve desk space. Any ideas?
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MBP + ACD = very slow
- Thread starter sv-mbpxs
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There's obviously a big problem. I'm running a late '08 C2D 15" MBP with a 27" ACD and I've never seen anything like that even once. You talked to Apple about it yet?
thats one thing i forgot to mention. It does get considerably warmer this way than the regular setup. However, it still isnt getting as hot as some that ive heard on this site. The hottest i had ever seen it in istat prior to the screen was 56C, now it gets around 70-75C.
The increase in heat isn't because the lid is closed; it's more likely the added work on the GPU to run the external display. Even so, those temps are perfectly normal and well within the operating range for your MBP.
Take a look at Activity Monitor to see what apps/processes/widgets might be causing the slower performance. Make sure you look at "All processes", not just "My processes". Also, look at your "Page Outs" and "Swap used" under System Memory.
Feel free to answer why it works fine with the lid open vs closed, then. Activity monitor is a moot point unless the OP wrote incorrectly but looks like he's running the same "things" closed and open. The keyboard opening is a passive heat exhaust. Run an intense render with the lid almost closed, and you can feel the heat coming out from around the narrow openings.
The keyboard is NOT a "heat exhaust". There is a solid sheet under the keyboard. The keyboard gets warm due to radiated heat, in the same way the bottom of the MBP gets warm, even though it's not used as an exhaust, either. All Apple notebooks vent through the rear, near the hinge. That is where all air intake and exhaust occurs.
Activity Monitor is not moot, since performance is directly related to what is running at any given point in time.
He's running the same things if the laptop is closed or open. AM is a moot point as long as what he writes is correct, ie that there is no issue when the lid is open. The issue is why is his performance dropping materially when the lid is closed. AM would be logically if he's reporting a systematic system slowdown.
I've taken apart my i7 when my bf spilled liquid on the keys, so I'm confused. A solid sheet of what under the keyboard? I'd look at a ifixit guide to double check what you think is under the keyboard. Mine has nothing solid at all unless you're saving yourself by calling the keyboard membrane itself "solid."
Just use logic. I'm aware of the fan in the back, but heat rises. Above the logic board is the keyboard membrane and that's all that stands between the logic board and the outside. There's not another sheet of solid anything. The heat does escape through the keys since heat wants to rise, and the membrane is breathable.
Instead of debating, do what I suggested before that my IT guy had me do. Run a render with the lid almost closed and come back in 15 minutes. You not only hear your fans running well but you will be able to feel the heat radiating out around the lid opening.
Here is the solid sheet:
It prevents any "exhaust", as you call it, or venting through the keyboard. Apple notebooks do not depend on the lid being opened to maintain cooling. If you want to use logic, Apple would not show you how to use clamshell mode if it was not recommended. They do, however, recommend that you not block the vents at the back of the notebook.
Heat radiates in all directions, not just upward. Apple notebooks are designed to work properly with the lid open or closed, in clamshell mode. If there is a problem with slower performance, the source of that problem is NOT clamshell mode. The OP has an issue causing the performance degradation, but it is NOT due to having the lid closed.
As the OP indicated, their temps are not unusually high. Whether the lid is opened or closed, those temps would not account for any slowdown in system performance.
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Just to verify, the same apps are running in both situations. While in clamshell mode i have the laptop in a twelvesouth bookarc so its vertical. Also I guess i can elaborate more on the problem, if im in autocad and try to rotate or move a 3d image i get the color wheel and it will stay that way for a while, also in iphoto if im in full screen with a picture enlarged beyond the size of the display and try to move it i get the color wheel. I wouldnt be so worried about just seeing the color wheel, but it stays for a long time, up to ten minutes at one point. This is very counter-productive for me which is a big problem.
Try setting up a new user account on your Mac and try the same things with that account. If you don't get the same symptoms, the issue lies with your user account. You can also check the cable used to connect to your display, as well as your display preferences. Also, you haven't reported back your findings from checking Activity Monitor, especially your page outs and swap used.
You might also try leaving your MBP flat, connecting to the display without using the bookarc (but still in clamshell mode), to see if you get any different results.
Clamshell mode actually runs cooler, because the laptop doesn't have to power the built-in display.
Let's see what happens as the OP troubleshoots, but you're misdirecting my point. I never implied laptops were not designed to run in clamshell mode. Clamshell mode is fine for 99% of uses, but there could always be a corner case where you're stressing the machine that clamshell does result in a performance hit *if* I'm correct about the heat.
I know that sheet, it is breathable so I still stick to my original POV.
Now, if someone is willing to run a test with a intense activity and record temps with lid open and closed showing the unit actually runs cooler with lid closed, I will happily eat my words because it will give me satisfaction to have my IT guy eat his words from before
I would do it myself but no longer have the i7.
No, the sheet isn't breathable. Air doesn't pass through a solid sheet. The vents are located in the back, not through the keyboard. The OP has already posted their temps, which are not unusually high, so your suggestion that overheating may be the problem doesn't apply here. If an Apple notebook gets too hot it shuts down. Overheating doesn't slow performance. Post facts to back up your statements, as I have. Hearsay from some "IT" person isn't credible, as I've encountered far too many IT workers over the decades who didn't know what they're talking about.
Thanks for all the input guys, i was actually hoping it was just some kind of setting i was missing or maybe a quick fix. I guess ill let apple figure out the problem. This is so frustrating, i switched to mac in november and long story short this is my third mbp since then.
I tried running it flat without the bookarc and its the same situation. Also, if i leave the laptop screen active and partially close the screen as suggested, no problem. But if i put it in clamshell mode and partially open the screen so that it is still only the display being active, the problem occurs.
If you have preferences, customizations, or other modifications to your account that could affect the performance, creating a new account gives you the opportunity to test without such things. After you test, you can easily delete the account.
Just an update for anyone interested, I spoke with an apple tech today. He had me try a few things including checking the hdd which turned out to be damaged, i repaired it but the problem persisted. Then he had me reinstall osx to see if it was an application causing the issue and then restore from time machine. Then he told me to call back if this didnt solve my problem, and thats when it went down hill terribly fast. After the install was done the computer was extremely sluggish and this was with just osx on it. I then did a restore from time machine, back to a date before any problems started occuring. It installed and asked me to restart and failed to start. It gets to the white screen but the apple never pops up, and there is very faint white noise coming from the speakers that correlates with the hdd spinning. Also it will not accept the boot disk at this point. So i guess ill be calling back tomorrow lol. I am quite impressed with the way apple is handling everything though, he told me that if it was a hardware issue they would fix it. I told him that i didnt really like the idea of having a 2 month old $2000 "fixxed" computer and he said that was resonable and that getting another computer shouldnt be an issue. I will probably try to get a different model if possible since ive had bad luck with this particular model.