If IE is using 90% of your CPU then there is something wrong with IE or something in the configuration of it. I've never seen IE use that much unless it's processing something or is hung up on something. Normal operation of IE or any browser should work well under that percentage.
Seems that Chrome may not be that beautiful in this adaptability if he Google can't keep it working on various devices.
This devices is Phased out:
http://forums.dlink.com/index.php?topic=50152.0So as it gets older and browsers graduate in development, I presume that support will wane at some point. You might keep a known working supporting browser installation program on hand and backed up for future use. This maybe the case where you might have to use an older browser to manage the DNS.
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You might try Opera Next, it's bases on Chromes engine as a test and see if it works. I personally don't use Chrome as it's been known to causes problems not only with connections with devices, also cause devices to become bricked during FW updates.
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Yes, 3rd party Security SW like AV, Firewalls and browser add-ons can impact how they connect to devices. I keep having to remember to disable ad-block on some of my devices.
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