These weren't made for long term use as in unplug, plug and repeat so test this laptop on other HDMI monitors and displays.
Short of having the laptop repaired you can try one of those USB to HDMI cards. Example:
https://www.amazon.com/Cable-Matters-SuperSpeed-Adapter-2560x1440/dp/B004MS0DIK
To sum up the problem in a nutshell :
I connect the laptop to the tv via a HDMI cord, and on the TV it is channel HDMI 3.
I also have a Telstra TBox attached to the tv.
last week the HDMI 3 channel showed as black screen when i plugged it in.
After unplugging HDMI cord 3 times and replugging, turning off tv and turning back on 3 times, turning on and off laptop 3 times also, i totally disconnected TBox at wall and tv completely then left it overnight.I used the tv as normal tv without the TBox on channel TV on screen. Next day i reconnected and replugged all. The HDMI finally worked.
A few nights ago same problem (black screen on TV channel HDMI 3)except this time HDMI will not work at all now full stop.
This time I did all as above but also changed HDMI slot on tv and tried HDMI 1 and 2. TBox is in slot HDMI 1.
I tried the laptop on my sons tv - lo and behold the computer screen shows up on his TV- although there is no audio coming from the tv still, no matter what.
Back to lounge room TV and - nope, HDMI is not working.
So cord is pretty new and I tried 3 different cords as i do have 3 HDMI cords.
(added info is sound through tv does not work and has not for some time using HDMI cord to tv - i also attach a small "music angel" portable speaker box to laptop to achieve sound. Sound does work on laptop - it is just not loud enough.)
Friend staying a few days today has plugged her Laptop into the TV and her Laptop works on HDMI channel 3 no problem. But no sound through the TV. Her sound is loud enough on the laptop though.
I have noticed when i plug in HDMI cord the laptop screen does flick off and straight back on like it knows to change to tv screen setting....although tv channel remains black.
Laptop is a: OS Name Microsoft Windows 7 Home Premium
Version 6.1.7601 Service Pack 1 Build 7601
System Manufacturer Hewlett-Packard
System Model Presario CQ62 Notebook PC
System Type x64-based PC
Processor AMD Phenom(tm) II N970 Quad-Core Processor, 2200 Mhz, 4 Core(s), 4 Logical Processor(s)
BIOS Version/Date Hewlett-Packard F.29, 7/04/2011
TV is a : Panasonic Viera TV: Model Number TH-L37U2
( another issue - I do not have original remote control to access viera tools. I bought a Universal Remote Control : One For All urc 7110 - although i cannot access Viera tools as it is not the original remote. Also the TBox has a remote i use for the television when watching free-to-air )
All I would like is to be able to plug in Laptop HDMI cord and watch stuff on the big screen without fighting for it or tears!
Thanks for any advice
Mandy

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