Internet painfully slow on one mac but fine on all other devices.

[emilybrearey]

Hi all.

I am having connectivity problems on one Macbook Pro, but not another. It appears to be hogging a lot of bandwidth with something in the background because once Problem Mac is connected, all the other devices on the network slow way down. I've been on the phone with Time Warner Cable (my ISP) all morning have determined that it's not a problem with our internet connection.

Here are my specs:

Problem Mac
MacBook Pro (13-inch, Mid 2010)
Processor 2.4 GHz Intel Core 2 Duo
Memory 4 GB 1067 MHz DDR3
Graphics NVIDIA GeForce 320M 256 MB
Ookla Speedtest results:
Download - 8.97 Mbps
Upload - 1.13 Mbps

Happy Mac
MacBook Pro (15-inch, Early 2011)
Processor 2.2 GHz Intel Core i7
Memory 4 GB 1333 MHz DDR3
Graphics Intel HD Graphics 3000 384 MB
Ookla Speedtest results:
Download - 16.07 Mbps
Upload - 1.23 Mbps

Additionally, when the Problem Mac is connected to the network (but not doing anything to my knowledge), the Speedtest results for the Happy Mac are:
Download - 12.41 Mbps
Upload - 1 Mbps

After some Googling, I found that it might be a permissions problem so I verified and repaired the permissions, but the problem persists. I also tried changing the channel on my router. I have restarted both machines several times (every time I try a new fix).

Let me know if I've left out any pertinent information.

Thank you!
Emily

 

[Altemose]

Additionally, when the Problem Mac is connected to the network (but not doing anything to my knowledge), the Speedtest results for the Happy Mac are:
Download - 12.41 Mbps
Upload - 1 Mbps

Does the issue occur with both Wi-Fi and Ethernet?