Is it necessary to connect the turbo switch (older boards)?

[Elledan]

Some of you might remember the boards with the 'turbo' function. My question is whether it's necessary to connect the turbo switch to the pins on the mainboard, and what would happen if you don't do so.

Say, a 486 with the turbo switch set to 'off' runs at 16 MHz, when switched on at 66 MHz. What speed would the CPU run at without the switch connected?

 

[DSTA]

Say, a 486 with the turbo switch set to 'off' runs at 16 MHz, when switched on at 66 MHz. What speed would the CPU run at without the switch connected?

It's just a simple switch, so it would be running at the same speed as 'off' without anything connected.

If the case you want to use has no turbo switch, find out which is the fast setting (closed or open) and if needed just use a jumper instead of the turbo switch wire.

 

[Elledan]

Well, I got a couple of old 486's lying around, most of which have no turbo switch on the case. With these systems nothing is connected to the pins, not even a jumper, so I assume that the 'open' setting makes the thing run fastest.

I've never done much work on such old systems, so I wasn't exactly sure

 

[sandorski]

The turbo switch, as I recall, was kinda misnamed. It would toggle the system speed downwards when needed for older games and such, so you could probably get away with not using it. Whaty you could do is plug the reset button to it, test the system speed in both on/off, then unplug the switch and see if the system operates at full speed with it unused.

 

[Elledan]

Thank you, sandorski

BTW, in case any of you were wondering what in the world I want to do with a friggin' 486: this little beast is going to serve as a router. However, due to a serious lack of space, I'm forced to put this and some other systems of mine in rackmounted cases, which I'm designing and building myself.

 

[Lord Evermore]

Reset switch is a momentary switch. I'm not sure, but I think the turbo switch was similar to an AT power switch, in that it has to be set "on" or "off", not just a quick momentary switch to toggle the setting. Dunno, but you might want to verify it.

 

[Elledan]

<< Reset switch is a momentary switch. I'm not sure, but I think the turbo switch was similar to an AT power switch, in that it has to be set "on" or "off", not just a quick momentary switch to toggle the setting. Dunno, but you might want to verify it. >>

yes, the 'turbo' switch is an 'off', 'on' one.

A jumper would do the trick, though, but I'm fairly certain that keeping the pins open is the right setting for 66 MHz .