Dell Optiplex 790 bypass Press F1 during boot

[Nismog]

Bought Dell Optiplex 790 motherboard HY9JP to load macOS 10.12.6 on it.  Everything is working great except that I'm missing the air temp sensor and the front I/O panel so everytime during boot, it posts a message about these 2 missing items and I have to press F1 to continue booting.

Checking if it's possible to edit the BIOS to skip this error message and don't need to press F1.  It's currently running version A06 but any of the BIOS listed at Dell's support page will work for me:

http://www.dell.com/support/home/us/en/0...90/drivers

Thanks!

[Aalesund]

This is how I bypass all "Alert!" messages on my Optiplex 790 mobo:

Bypass: Alert! Air temperature sensor not detected.
You have 3 options:
1. Use Power LED or HDD Led - this will bypass the sensor but motherboard fan will runs on full speed (4500RPM, very noisy) because the themperature is out of range
2. Use 2.4K Omh Resistor - this will simulate ambient temp about 15°C and the motherboard fan will runs on 1200RPM (silent)
3. Use a real sensor if you really care about the ambient temp - buy cheap Digital Thermometer (like this: https://www.ebay.com/itm/123552743125) and take the sensor then connect red wire to positive and black to negative



Bypass: Alert! Front I/O Cable failure.


Also this is the other errors that are easy to bypass:

Bypass: Alert! Power Button Cable failure.


Bypass: Alert! CPU 0 fan failure. / Alert! Hard Drive fan failure.

[Nismog]

Thank you very much!

I've fixed the Front I/O panel and power switch issue.

I plugged my HDD LED connector into the air temp sensor pins.  The HDD LEDs are constantly blinking but I still get the air temperature sensor not detected message.


I have a case on order to fix the HDD fan error message.

Thanks again.

[Aalesund]

This is the easiest way to bypass "Air temperature sensor":
1. Use 2pin connector + cable from broken fan
2. Buy 2.4K Ohm resistor
3. Solder the cable to resistor, it doesn't matter positive and negative cables
4. Put it into your Mobo

Here is a picture:

[Nismog]

This is the easiest way to bypass "Air temperature sensor":
1. Use 2pin connector + cable from broken fan
2. Buy 2.4K Ohm resistor
3. Solder the cable to resistor, it doesn't matter positive and negative cables
4. Put it into your Mobo

Here is a picture:

Thank you.  I will try this!

[jozsef_kacso]

This is how I bypass all "Alert!" messages on my Optiplex 790 mobo:

Bypass: Alert! Air temperature sensor not detected.
You have 3 options:
1. Use Power LED or HDD Led - this will bypass the sensor but motherboard fan will runs on full speed (4500RPM, very noisy) because the themperature is out of range
2. Use 2.4K Omh Resistor - this will simulate ambient temp about 15°C and the motherboard fan will runs on 1200RPM (silent)
3. Use a real sensor if you really care about the ambient temp - buy cheap Digital Thermometer (like this: https://www.ebay.com/itm/123552743125) and take the sensor then connect red wire to positive and black to negative



Bypass: Alert! Front I/O Cable failure.


Also this is the other errors that are easy to bypass:

Bypass: Alert! Power Button Cable failure.


Bypass: Alert! CPU 0 fan failure. / Alert! Hard Drive fan failure.

Hello!

My name is Jozsef. I Have an Optiplex 990 and since when the IO frot panel 34 pin connector is broken there are 2 problems:
1. Front IO cable failure - solved as you wrote
2. The fans are very noisy (as you can see on the attached HWinfo printscreen):
   
In this printscreen there is a second Ambient temperature sensor which shows an incorrect 192 C value and I think this is strongly related with the missing IO adapter and probaly this is the cause for the noisy fans. How can I resolve the noisy fans?

Thank you,
Jozsef