27'' iMac is now very slow on surfing the internet!

[ciarals]

Hi! I'm writing here beacuse I have a problem. I have a 27'' iMac: never had a problem since january, but from today my internet (cable) connection works very slow. I thought it was my router, but with my MBP everything is fine: with the iMac I can't nearly reach the SpeedTest site.
I tried rebooting, shutting down, resetting the router, changing browser, changing DNS settings: nothing. Also the wireless transfer files between the MBP and the iMac is so slow: yesterday I transfered some video files 1MB/s, today 20 KB/s!!!
I've also tried using AirPort in the iMac: nothing. Is like the internet connection is gone. What can I do? Is my iMac broken?
Thanks for your answers. Bye!

P.S.: as if the above was nothing, I've updated Firefox to 3.6.2 and I can't open it anymore (in my MBP, of course, everything's fine).

[hippo206]

I am no expert when it comes to these kinds of things, but this exact thing happen to one of my mbp's once, and it was a ram issue. I took it in, and apple replaced the ram no questions asked, and everything worked well.

[redshift1]

Hi! I'm writing here beacuse I have a problem. I have a 27'' iMac: never had a problem since january, but from today my internet (cable) connection works very slow. I thought it was my router, but with my MBP everything is fine: with the iMac I can't nearly reach the SpeedTest site.
I tried rebooting, shutting down, resetting the router, changing browser, changing DNS settings: nothing. Also the wireless transfer files between the MBP and the iMac is so slow: yesterday I transfered some video files 1MB/s, today 20 KB/s!!!
I've also tried using AirPort in the iMac: nothing. Is like the internet connection is gone. What can I do? Is my iMac broken?
Thanks for your answers. Bye!

P.S.: as if the above was nothing, I've updated Firefox to 3.6.2 and I can't open it anymore (in my MBP, of course, everything's fine).


I occasionally had the same problem with my MBP and G5, I was never able to diagnose the problem but on the good side it disappeared.

[JoEw]

I had this issue when i first got my 27" quad core imac but somehow it fixed itself. Make sure you have the latest mac software update installed. Try using different browsers chrome, firefox, safari, opera. See if one of those browsers have higher speeds then others. These are the things i did and somehow my internet speeds returned to normal.

[ciarals]

Thanks for the answers but I can't wait randomly for my iMac to start working. Do you think that a PRAM reset could work?

[stridemat]

OP its worth a try to do PRAM reset

[ciarals]

I've resetted the PRAM and also the network settings: of course, nothing changed. I don't know what to do...

The only positive thing is that I've managed to make Firefox operative again...

[pilot1226]

Is it possible that you may have erroneously typed a password for your network connection? Does the problem exist for both wired and wireless connections?

Reason I suggest the former is because on Windows PCs, if you type an incorrect passcode for WEP or WPA, it will sometimes still let you connect and pull a DHCP IP from the router, but you get a "Limited Network Connectivity" notice which severely cripples your bandwidth. I'm not sure that this happens in OSX also, and I haven't really attempted to duplicate it.

I'm curious as to if this happens for both wired and wireless. Or, if someone on your network is hogging a lot of P2P resources. You sound like you know what you're doing, but just to throw that out there, if you are on a wireless network, you ARE changing the default SSID and Admin Login, yes? I've seen a lot of cases where people left the defaults on, someone nearby logs into their router and changes the QoS to exploit P2P transfer.

One last step - simply your network. Temporarily remove the router from it... connect your computer directly to your cable modem and powercycle the network, letting the modem remain off for about 60 seconds before you turn it back on. If your speed is good plugging in directly, it's either an issue with the router itself or the way your computer(s) are communicating with your router.

[ciarals]

Hi! Thanks for the answer. I have the same problem using the Wireless or the Ethernet. Of course I've changed the SSID and also the password, but I haven't changed the router settings since 5 months, and the problem appeared yesterday...
I haven't any modem, the router is cabled directly to the line. Then there's an ethernet cable to my iMac and the other peripherals (PS3, MBP, etc...) connects to it via wireless... and connect perfectly!