If you've got spare cable(s) then you could hobble the DDC clock and data pins that's 6 & 7 on DVI or 15 & 16 on HDMI
With the lack of EDID data, it's anyone's guess whether the PC will assume
1024x768 or 1920x1280, or refuse to play at all.
On the main AV system, I have an HDMI selector switch. 4 inputs, 2 outputs. Any input to any output, or both at the same time. Main use is to be able to use the various STBs on a second TV.
Nicked it and inserted it in the TV HDMI feed here (only as a sort of buffer amp)
Everything now working as should. TV showing the same res as the monitor. So it is obviously stopping the TV talking back to the PC video card.
Quite pricey, though. What I need is something that does the same but smaller.
Bought a 4k HDMI switch used off Ebay for not a lot. 2 in, one out.
That seems to have done the trick.
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