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Bmcdanold
10-06-2000, 06:27 PM
I just found an old 486 33mhz machine by unisys. Its really small but i want it to work because it uses 72pin simms for ram and it has onboard scsi! I push the power button but nothing. The power light comes on. Im wondering if the CPU is broken, its an onboard one that is 33mhz, but theres also a socket 2 zif slot for a "upgrade" cpu. I cant seem to figure out what is the problem with it. Where can i get documentation on unisys computers, or am i looking at a failed motherboard that is dead and will never come to life again hehe. All of the jumper setting are on the case inside but i set them all right and still nothing. Not even a beep...(and i know thats never good!) Any help would be appreciated, otherwise this boards gonna be a permanent part of my dead mobo collection.

Paleo Pete
10-06-2000, 09:38 PM
Check it with different memory, known good memory if possible, and maybe another CPU. I'd bet it's a dead motherboard though...

Oh, also pull the video card and reseat it, and push all the chips on the board firmly into their sockets. With a board that old, socket creep is a definite possibility. Set the board on a flat surface to do this, don't leave it in the case, to much possibility of bending the board too much and breaking it or breaking a circuit. And take the standoffs out first too.

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If you had everything...Where would you put it?

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Bmcdanold
10-07-2000, 12:58 AM
Well i opened it up again and as it turns out, there is no internal speaker and nowhere to put one! Is there any way i can post pictures in these discussion groups?

Bmcdanold
10-07-2000, 01:05 AM
Actually it does have an internal speaker, it was just very small and well hidden. It has onboard video, ps2 mouse, keyboard etc. Also when i turn it on, the power supply fan barely runs and nothing turns on except the hard drive does a "testing" type sound.

Paleo Pete
10-09-2000, 01:13 PM
Sounds like a power supply problem. Check around, power supplies are available at computer shops, or places like CSO (http://www.computersurplusoutlet.com) and Pricewatch (http://www.pricewatch.com) online.

To post pictures, you'll need to upload them to an online server such as Zing (http://www.zing.com) and post a link to them using UBB code. check the "Click for Details" link for instructions on using UBB. Try to keep them as small as possible. I think .jpg files compress the smallest.

If the fan barely runs, the shaft that turns the blades is gummed up. You might try removing the fan and oiling it with some household oil, like 3 in 1. Use only a drop or two. Be very careful tinkering inside3 the power supply, it has capacitors that hold a charge for days, and can make you very unhappy if you touch the wrong spot.

------------------
If you had everything...Where would you put it?

Computer Information Links (http://www.geocities.com/paleopete/)