mm said:I hope this is a good forum for this one!
Why don't Dell computers have reset keys?
How do the users live without one? I don't use mine often but when I
need it, I really need it.
The mobo layout provided in the Dell manual doesn't seem to show a
place where a reset switch could be connected, but perhaps there is
A logical place for a connection, would be on the PANEL header.
So where the front panel wires connect to the motherboard, would
be the best place to look for a RESET pin if one was available.
They may choose, in their documentation, to not label it. But
the reset logic still exists. It has to, as the board has to be
held in reset, until PWR_GOOD from the power supply says it is
time for the system to start. Computers are designed to wait
until all power is stable, before starting.
The existence of a RESET button, implies your design is flaky
enough to need one. It means the design crashes enough, to need
a RESET button as a crutch for system recovery. Removing the
button is then a "marketing feature", rather than having
any technical merit. The system may still crash, but it means
you'll be using the power button instead.
If my Apple computer doesn't have a reset button on it,
then the Dell computer can't have one, either
You can try looking at a reference schematic, to see how they
wire up reset on a motherboard.
If you look at PDF page 7 here, there is a whole page devoted to
tracking where the reset signal goes. The "FP_RST" signal in
the lower left hand corner of the page, is what the front panel
button connects to. In this design, it interfaces with a pin
on the Intel Southbridge. I think a glue chip, distributes reset
to other buses and places. In terms of just "reaching into your
computer and connecting to reset", you'd have to find the equivalent
of that pin on the Southbridge.
Another thing of note, is computers are not guaranteed to honor
the RESET signal. As a digital designer, one of our "ten commandments"
of design, is a design must respond completely to the activation
of the reset signal. I've had computers before, where this requirement
is not met (Nforce2 based). So if you're thinking RESET guarantees
a smooth and orderly restoration of sanity, you'd be wrong. As another
example of that, the SATA drive is not guaranteed to be reset by pressing
the RESET button. An IDE drive, and its associated ribbon cable,
have a discrete reset signal. The IDE drive will always get reset.
I've had a SATA drive before, that did not respond to reset, and
I could not detect it in the BIOS until the computer was power cycled.
You can wire up your RESET button if you want, but there are still
going to be occasions where it doesn't work entirely. And the computer
industry should hang their heads in shame because of that...