Got a 22" CRT and after connecting it to a 486 and starting up Doom I thought the monitor/cable/connector was faulty as the picture was practically "wholesale" purple.
By accident I got Win95 started and surprise... everything looks ok there.
Is this due to a fault or common behavior for larger screens? Similar thing can be observed on the 21" SUN I have.
Hm. I haven't really used 22" CRTs, but my father's old 20" CRT showed a similar purple/violet screen
whenever it was switched on (this happened in the CRTs later lifetime).
It was a cold solder joint, my father said. After a few minutes, the pciture was in full colour again.
He also ran Win95 on his 386DX40, btw.
"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel
//My video channel//
Ok, I'll look into that.
The previous owner said something about a bad cable which meant he noticed something off and only took the simplest solution into account.
The strange thing is that in the bios screen it's looking normal and in Windows when one changes the individual channels the green one is as responsive as all the others... cranked up it "greens" away which shouldn't be possible if the gun or another component is faulty.
Perhaps it is somehting else then.
The green channel uses pin 2, which is also used for monochrome video (source).
If the monitor was not correctly recognized by the VGA card through DDC or Monitor ID bits, strange things couldn happen.
Maybe the monitor receives no signal or a grayscale signal over the green channel (pin 2).
This would make sense insofar, that your issue vanishes once an application (Win95) is in control (overwrites VGA BIOS settings).
I know, this pretty far-fetched. It's just an idea, anyway. 😅
Maybe it helps to disable "VGA palette snooping". It also caused funny things in the past.
Like an messed-up colouring of the Win95 boot animation.
"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel
//My video channel//
wrote:Perhaps it is somehting else then. The green channel uses pin 2, which is also used for monochrome video (source). […]
Perhaps it is somehting else then.
The green channel uses pin 2, which is also used for monochrome video (source).If the monitor was not correctly recognized by the VGA card through DDC or Monitor ID bits, strange things couldn happen.
Maybe the monitor receives no signal or a grayscale signal over the green channel (pin 2).This would make sense insofar, that your issue vanishes once an application (Win95) is in control (overwrites VGA BIOS settings).
I know, this pretty far-fetched. It's just an idea, anyway. 😅Maybe it helps to disable "VGA palette snooping". It also caused funny things in the past.
Like an messed-up colouring of the Win95 boot animation.
This sounds like a pretty good tip.
In Doom, for example, everything's SanFrancisco'd but once you pick up the hazard suit(green palette) it looks normal.
I once had a 20"electrohome VGA monitor that had a very similar problem. It turned out that the fancy "BNC" cable it used was defective.
"Will the highways on the internets become more few?" -Gee Dubya
V'Ger XT|Upgraded AT|Ultimate 386|Super VL/EISA 486|SMP VL/EISA Pentium
Ok, I retested this with the "palette snoop" feature toggle'd and it does not make a difference - the Matrox seems to exhibit this issue in DOS nonetheless. I tried an Ark1000 and this one is way better... the love-tint is gone from the DOS prompt and in-game the picture exhibits way better color temperature.
BUT I still feel that the overall hue is off. One can only regulate red and blue values but not the green one.
Could the "green gun" be weak/the tube in general be worn out?(excuse my meager knowledge of how CRTs work) If so is it realistic to find a replacement or is this typical of an enthusiast's "somehow possible solution".
@CHIPS: I'm running the CRT with a standard vga cable but already ordered a component one and will report my findings.
Update:
it seems that the monitor just exhibits this kind of reproduction in DOS - no matter how high the resolution.
The picture is rather dim and lacks green - when in Windows the picture is pretty good and normal looking which disqualifies the option of a real technical problem most likely.
I put the screen into a closet and will test it later when I have the VGA/BNC cable. Put out the SUN/Sony and its picture is WAY better no matter if DOS or Windows.
