Computers as Time-Keepers

Ron Eggers

SPFG, Supreme Picture Framing God
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It's my turn to ask a question. Why is a $19.95 Timex so much better at keeping accurate time than a $2,000 PC?

I know that keeping time isn't the primary function of a PC. But many file-management functions, like syncronizing the home and office PCs, are highly dependent on accurate clock times. I'm looking at the clock on this, our household's second-string PC, and it says 7:30 pm. It is, in fact, 9:03 pm and I set the clock yesterday!

I know there are utilities that will automatically synchronize your PC's clock against the atomic clock at the naval observatory each time you go on line (within a millisecond.) And, while the extreme geekiness of such a utility may appeal to me, I have to wonder, "Why is this necessary?"

BTW, the battery on this PC is fine.

Ron
 
This has always amazed me! Never have had a PC that could keep time. Not even close. High on the computer pet peeve top ten list here.

Now I've switched to an Apple iBook and I'm amazed because it keeps up perfectly with my atomic clock. But I think just for grins they made it so the clock pauses when you shut the lid and the computer goes to sleep. If you look at the clock within a few seconds of waking it up, it shows the time it went to sleep. Sometimes it the simple things that please me. Can't tell you how nice it is to have a computer that keeps time- kinda makes you trust it for real processing work.

Oh yeah, I also like the way it doesn't remind me that it has adjusted for daylight savings time.
 
This computer has XP. I like it, so far. It reminds me a little too much of NT, though. It takes a lot of control from the user.

It DOES have an excellent clock! I've kept a wary eye on the time, and it keeps up nicely. Don't know if that's a function of XP, or Gateway...
 
Ah the computer clock, what a concept.
The problem with computers and clocks has to do with the way a computer computes time. It uses the bus speed and the CPU's internal "Clock" to keep track of normal time. It gets really deep and has to do with even your power supply. Newer computers are much better at this than the older ones and newer software have better routines to handle it. The "Clock" is a calculation of cycles through a "Clock" routine. It is assumed that the time period through the cycle is the same every time. Using cycles/second the routine calculates time, however this can change depending on software you are running, and millions of other little things, therefore it isn't necessarily accurate. The faster and newer the CPU and MB the better the circuit and the more accurate it keeps time. Mine is still within about 10 seconds from when I set it in December.
 
Thank you, Jerry. Most of that actually made sense.

Don't go too far away. I have more questions.

Ron
 
So, does that mean that one of the trouble-shooting routines might be to check the dirtiness of your power supply?

I keep running into hints which tell me that a UPS is a good thing to do.
 
P F,
If you have power trouble, brown outs, lights dimming, and all that rot. A UPS is a real good thing. If you get one, get one that has a little battery time in it. That way if the power goes out you can shut down the computer before the UPS shuts off. However some of the more expensive UPS's actually have software that will shut down your system for you, and turn it back on in the morning. Couple Hundred dollars ought to do the trick.
 
So, computers aren't good time keepers. The important thing to remember is that a computer is a tool. Every tool has a use (or uses) at which it excels, and others which it can perform, but not neccesarily efficiently.

In our business we have a shaper and a moulder. While you can run moulding through a shaper (we used to), it is almost infinately more efficient to use the moulder for our normal sized runs of a thousand or more feet. But when we need to make a 3 foot piece of one-off moulding we'll use the shaper. Either job can be done on either machine, it's a matter of choosing the best machine/method for the job at hand. I'm sure you framers have similar scenarios you can relate to.

My suggestion is to just install a utility (as you mentioned) to update the time online and be done with it.
 
Or a watch
 
On all of the many Macs I have owned over the years and also on the POS Windows machines we use, the "date and time" function draws power from a small lithium battery on the motherboard. On a Mac, my experience has been that the battery will go suddenly dead somewhere between 1-3 years down the line. The Windows machines batteries have lasted longer and died more slowly, gradually losing time in the process. Does anyone know why these batteries are even necessary? On a desktop computer that is always plugged in, why can't the clock run on AC power?
 
Bearcat, I turned on my Mac one day and the date had reset itself to 1958...or something like that. Only then did I discover that the clock ran on a battery. The reset date is a birthday or the like of a significant person in the Mac world. True as far as you know? That was told to me by the Mac tech.
 
The battery in the computer only keeps the power going to certain parts of the 'puter. The clock circuit and the CMOS. In a PC the CMOS has the clock circuit and all your setup information for your hard drive. It also contains the address of the boot track on the hard drive. When the battery goes this info is lost and needs to be reset in the setup program (Hit delete to Enter Setup) on PC's. Newer motherboard BIOS is pretty easy to keep track of things because of the autosearch function when searching for a hard drive. However if the battery goes all of your settings that are changed from default settings need to be redone. AC power actually enters the PC in the Power supply, the supply then regulates and changes voltages to DC at specific voltages. The on and off button turns the power supply on and off. The power supply would have to be on all the time if the clock circuit were to work through the AC. Might as well keep your computer on.
 
MerpsMom-

When a Mac battery fails, the date defaults to a specific date in 1956 which I have read is the birtday of one of the original Mac programmers. Just one of those little Apple in-jokes.
 
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