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hello new owner of a ibm5155

al1980

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Sep 15, 2012
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15
hello my name is andre and i recently got a ibm 5155. and i am looking to upgrade a few things on it.

also i like to know if a v20 will conflict with a math coprocessor?

if you guys can suggest a list of stuff for this computer i be thankful.

here is a few photos of the computer.

IMAG0123.jpgIMAG0126.jpgIMAG0127.jpgIMAG0128.jpgIMAG0129.jpg
 

modem7

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Welcome to these forums.

The rear 15 pin connector marked "MOUSE" is probably a game port.

Significant 5155 information is at http://www.minuszerodegrees.net

also i like to know if a v20 will conflict with a math coprocessor?
Not that I'm aware of, but upgrading the 8088 CPU to a V20 can in some cases cause other issues.

if you guys can suggest a list of stuff for this computer i be thankful.
One possible upgrade is to remove the second floppy drive and then fit a hard drive and controller.
As pictured at http://www.minuszerodegrees.net/5155/photo/5155_mine.htm
 

al1980

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Sep 15, 2012
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if the v20 will cause problems i won't get it.

i like to know how to get software for this computer.

is there ways to put software on new blank floppy disk? beside buying old floppy disk off ebay?

is there a faster 8088 that will fit this computer?

the guy who i buyed this from said something was wrong with one of the floppy drives.

this was his quote

" one of the two 5-1/4-inch drives is not working, or at least it only works intermittently since we were just able to get it to boot the orientation disk in drive A."

i did not test the 2nd drive. i will tomorrow.
 

ibmapc

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Not that I'm aware of, but upgrading the 8088 CPU to a V20 can in some cases cause other issues.

I think Modem7 is saying that the V20 is incompatible with a very small number of programs. But I would not let that stop me from upgrading to a V20. The V20 works perfectly in my 5155 and coexists just fine with the 8087. The problem with Drive B is probably caused by sticky carriage rails and/or dirty heads(easily fixed with a careful cleaning and lubrication). You should clean and lube both drives as soon as possible. A very small amount of silicone lube applied with a Q-tip to the carriage rails does wonders.
I too would like to see pics of the inside.

Welcome to the forum. There are plenty of helpful members here so don't be afraid to ask for help here.

Regards,

Greg
 

modem7

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if the v20 will cause problems i won't get it.
You turned my "can" into "will".

I think Modem7 is saying that the V20 is incompatible with a very small number of programs.
Yes, software and firmware.

But I would not let that stop me from upgrading to a V20.
I agree.

is there a faster 8088 that will fit this computer?
It would not result in a performance improvement - the motherboard would run the 'faster rated' 8088 at the same speed as the old 8088.

is there ways to put software on new blank floppy disk? beside buying old floppy disk off ebay?
For some techniques of transferring software from new to old PCs, see http://www.minuszerodegrees.net/transfer/transfer.htm
 

pearce_jj

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I'm developing a storage option ideally suited to the 5155 - see here (a blatant plug since al1980 is a new member, but hey :) )

I'd not bother with the V20 personally, since after all there are any number of faster portables if that is the goal. I would though strip the machine down and give it a good clean, and probably replace electrolytic caps in the PSU (might find some RIFA filter caps in it too).
 

ibmapc

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I would though strip the machine down and give it a good clean, and probably replace electrolytic caps in the PSU (might find some RIFA filter caps in it too).
Naw, don't bother with the caps in the PSU unless it gives you trouble. The 5155 PSU is pretty robust. I've tried to kill mine a couple of times, but it keeps on goin'. (Do give the old girl a good cleaning though.)
I'd not bother with the V20 personally, since after all there are any number of faster portables if that is the goal.
As far as speed goes, people don't buy the 5155's for speed. They buy them because they are True Blue IBM and they are cool. But there is nothing wrong with trying to get a little more performance out of one by putting a V20 in it. The V20 will also let you run a few programs that won't run on an 8088 due to it's enhanced intstruction set.
 

al1980

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my knowledge of computers is mostly having new custom made desktop computers and small upgrades to my laptop. things like psu and rifa are all new to me. in short this is unknown to me.

older computers i known about are ones that had a keyboard and computer together. the monitor and the B drive where on the outside connected.
 

ibmapc

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Those pics look really nice! It looks pretty clean inside.

how can i remove the cpu correctly?
FIRST Ground yourself. There are a lot of static sensitive parts in there.
The important thing when removing the cpu is that you don't bend any pins. The best way to accomplish this is to remove the motherboard(it can be done with the motherboard installed, but you have better access with it out of the case) and use an IC extracter. Before removing the moterboard, all expansion cards and both floppy drives must be removed(you need to clean and lube the carriage rails anyway). A 1/4 inch drive ratchet with the appropriate socket helps when loosening the inner floppy scews. When you put the V20 in, be carefull to align the pins with the holes in the socket before carefully pressing it all the way down into the socket (the notch on the end of the IC must line up with the notch on the socket.). Don't push to hard. If it doesn't go fairly easy, you probably don't have it lined up correctly and you'll bend pins if you force it. Again this is difficult if you don't remove the motherboard. Radio Shack makes an IC inserter that helps but you still have to align the pins. Your great pics should help you figure out how to put it back together.
 
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Shadow Lord

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What do you guys recommend for lubricating the rails? Also do you actually do this regularly? To be honest I have never done it and even my 5150 drives (which are original) continue to run w/o a hitch. I know all oil will break down, get dirty, get sticky, but if its working fine maybe it is a case of leaving well enough alone?
 

ibmapc

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What do you guys recommend for lubricating the rails?
I use isopropyl alcohol to clean then very small amount of silicone lube with a Q-tip.
Also do you actually do this regularly?
Maybe once every 15 years.
To be honest I have never done it and even my 5150 drives (which are original) continue to run w/o a hitch. I know all oil will break down, get dirty, get sticky, but if its working fine maybe it is a case of leaving well enough alone?
The floppys on my original 5155 started acting up about 5 years ago and cleaning and lubing the rails fixed it right up. I also bought a 5155 from ebay a while back with non functioning drive A. Cleaning and lubing the rails fixed it right up.
The Qume drives tend to get sticky rails. Maybe the stepper motor is a little weak or maybe the carriage rails aren't well designed or lubricated in the first place.
 
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