If your new front projector is 1080p (lo-res), your old HDMI cable will do (most likely).
But with a new UHD TV or front projector (4K), you need @ minimum a
HDMI High Speed Cable (and with version 1.3 or 1.4 there is still no guaranty, if not high speed). Best is to get a HDMI high speed cable...one not too old.
And! Depending on your UHD TV or 4K front projector, the length of the HDMI cable, even with a 4K HDMI high speed cable, it could hit a bottleneck, and not working. For long runs (30-60+ feet) you can get an active (power booster) HDMI cable: •
http://www.hdmi.org/installers/longcablelengths.aspx
•
https://turbofuture.com/computers/do-i-need-hdmi-cable-4k-hdmi-20-guide
•
https://en.wikipedia.org/wiki/HDMI
** If watching 4K Blu-rays and/or true 4K video content from some TV/Internet service providers on a true 4K TV or screen ?
High Speed HDMI cable.
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*** The Epson PC 6040UB is NOT a TRUE UHD (4K) front projector. It supports a HDMI 4K connection, but doesn't project true 4K images.
•
http://www.soundandvision.com/category/projector-reviews
The true
native 4K front projectors that I am aware off cost considerably more than $4,000 (MSRP). Sony has one for $25,000+ (MSRP).
Other Sony, JVC, Epson, ...less expensive 4K projectors upscale to 4K, and are NOT NATIVE 4K.
•
http://4k.com/projector/
I'm waiting for a true native 4K front projector for $5,000 or less. Perhaps by the year 2020.
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?
http://hometheaterreview.com/the-state-of-4k-front-projection/