celticfan11

What was the point of the "Turbo" buttons on the old P1 PC's? I see alot of them at once client's place i work at. And they do nothing, and when we had a PC that had a turbo button (50 years ago) it did nothing either.

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kcnychief

Turbo Button
A leftover from machines of five to ten years ago, the turbo switch still remains on many cases, even though it really serves no purpose any more. In the early days of the PC, there was only IBM, and there were only a handful of different speeds a PC could run at. Early software was written by programmers who believed they were writing it to run on a machine of a specific speed. When newer, faster machines would come out, some of this software (especially games) would stop working properly because it would run too fast. Turning off the "turbo" function of the PC (which meant anything that made it run faster than an IBM of a particular era) would make the machine run slower so this software would work. In essence, it was a "compatibility mode" feature, to slow down the machine for older software.
Now, there are dozens of different combinations of processor types and speeds. Software cannot rely on knowing what the speed of the machine is, so most programs use speed-detection algorithms to determine how fast the machine is. The turbo button no longer serves any useful purpose, and in fact on many motherboards there either isn't anywhere to connect it, or there is a place but the motherboard does nothing when you press the button. The best use for this button is to never touch it, or use it for some other purpose. Some older machines will still slow down when the button is pressed, and if you press it by accident your machine will lose performance; it can be surprisingly hard to track down the problem, since it seems that the front of the machine is the last place anyone appears to notice anything. :^) You can correct this problem if you find yourself doing this frequently.
Fortunately, the turbo button has all but disappeared from modern system cases, especially newer NLX, ATX-family, and WTX form factor systems.

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celticfan11

excellent. I want one on my system now. I want to slow down my pc.

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Steevo

I used to run a PIII System in a really old case, with a turbo button. I plugged it in so it would light, and not do anything else.

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kcnychief

Mmhmm, I as well enjoy lights

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Petros

I had an old Pac-Man clone that I played on my Pentium DX2-66. It ran like it was on crack until I hit the turbo button!

Steevo

Ahhh, old stuff.

We still have a ethernet-twinax converter that runs a 486, and used to have a 80836 IBM console inline (didn't work) as no one was smart enough to just put connector inline. (They thought it still did something)

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VenomXt

i still have a working apple 2 c computrer in my closet. .hehe green screen and had to load the os from floppys everytime you booted. hehe

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Admiral Michael

Always wondered the purpose of that button

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vern

Lots of older software used CPU cycles for it's timing. With the turbo button on, older software ran like a rat on speed. This happened to one of my favorite games, the first Theme Park. It ran so fast as to become unplayable on my newer machine, which didn't come with a turbo button. Emulators such as DOSBox I think can emulate this though.

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Son Goku

Sounds somewhat like what happened when I used to play Deadly Tide (an old Direct X 2 game). Thing is, it didn't speed detect, or break. It just got to running faster. By the time I was on an Athlon Tbird 1 GHz with 384 MB RAM and a GF2 GTS, the thing played so fricken fast I literally had to be on the edge of me seat, in "super concentrate" mode to keep up with the thing. I did adjust so I could play/react to the thing that fast. BTW, the thing was designed to play on a Pentium 75 with far less RAM, and a much older gfx card...

I never did try it on my current AXP with a Radeon 9600...and a A64 with 7800 SLI would probably be funny to see at least once