|Presumably you have dual o/p vga adapter; not using a splitter cable/box?|
For clarity - suggest call working display "A" and the faulty one "B".
Orange light and the word "sleep" here suggest the monitor "B" is in sleep/standby mode?
There may be an option in the on-screen menu listing for "B" that activates (or de-activates) sleep mode; although I don't recall having seen that on any displays I have ever used.
Some (most/all) current monitors go in to sleep mode when no signal incoming. I have an elderly (by current standards) Acer 19ins tft display that does that. Which does suggest there is a loss of signal incoming; as if it was merely the contrast that was set to zero - and there was a signal incoming - the display would remain black; the monitor would not go into standby, and its light would remain green - not go orange?
Things to check: switch the monitors around so that each monitor (with its current cable) is on the other monitor's vga o/p connection; do this on the vga card outputs. This means that A is now connected (with its own/current cable) to where B was and B where A was. Does the "B" monitor now work - or at least the orange/standby light goes green and "A" now goes into standby/orange light? If so - possibly you have a problem with the vga o/p to which "B' was originally connected?
If things remain as posted - "B" still goes into orange/standby mode - restore connections to as before on the vga outputs, then switch the cables (only) so that each monitor is now using the cable for the other monitor - with cables connected to the vga outputs as originally. Does the "B" monitor now operate OK - at least the standby light goes green, and "A" possibly (probably) goes orange/standby?
If "B" (using the cable from the other/working monitor) now seems to work (goes green mode rather than orange/standby - even if no display (screen remains black); and "A" (using the cable from the faulty monitor) now goes orange/into standby... you have a problem with one of the vga cables - possibly...
If condition persists (i.e. the vga o/p where "B" was connected originally won't work with either display in above tests... which means that both "A" and "B" will go into standby/orange light condition) then have a look at the vga display options on the desktop itself. Possibly vga-o/p for "B" has been disabled...?
Not on a windows system just now - so from memory; right click on the desktop to bring up the assorted options where possibly you also have an add-in utility that allows you set all functions on the display from there. My elderly (very) Acer Aspire 1692wlmi has an ATI graphic card etc. and that has an add-in utility (accessed via a tab) that allows all settings to be tweaked - for both the laptop display and the external 19in tft I have connected to it (sometimes). One simply selects the appropriate monitor icon in the control panel that is accessed via a tab on the options display as above (if two displays are active, or intended to be).
Incidentally the Dell logo display comes up via the on-board basic VGA adapter - not via the vga card you have installed. That add-in card is only active/available after the OS boots up fully. Which does have me inclined to suspect the card itself is either faulty, or one of its settings may have changed (as above). That can be checked/restored/reset etc via the tests suggested just above?
Equally - if display "B" was provided by Dell - or is a Dell branded model - then the Dell logo will come up regardless... My Acer 19in tft shows the Acer logo with nothing connected to it, no any active signal incoming; then it goes to black and standby/orange light (until a signal arrives). Which would explain the momentary Dell logo display; and suggests either a vga cable problem or a vga o/p problem(or a setting in the vga controls via the desktop options)?
message edited by trvlr