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View Full Version : Authenticity vs Improvement



Druid6900
March 12th, 2007, 02:35 PM
I like to run this poll to see what serious collectors are looking for.

Case in point, I have 2 Commodore PC40-IIIs and an IBM PS/2 type 8555 that require the replacement of the DS1287 RTC.

Now, I have access to both the DS1287 and the newer DS12887, and I'm interested in finding out a) weither collectors would rather have the original part or the improved part and b) weither they prefer the part to be installed the original way (soldered to the board in the case of the PC40) or have a socket inserted for replacement convenience.

dongfeng
March 12th, 2007, 04:26 PM
Personally I would solder in a socket. If the computer is to be preserved, then this would enable easy replacement in the future.

Also, if the socket is used it would not matter on which replacement was used, as they could be easily swapped. Socket would appear original too, only the most die-hard would notice :)

Mad-Mike
March 12th, 2007, 04:26 PM
Unless it involves "non-reversable" modification, except in special "cases", I prefer improvement. Main reason being to address the machine's shortcomings...

Take for instance, my XT. I could have bought an MFM Controller and an ST-506 hard disk, but what about several years from now when they become even more rare, that's why I picked SCSI instead. Same thing goes for the 640K RAM upgrade (which involved soldering) I could have also sought out an original IBM XT Chassis too, but I figure, in the mean time, as long as it works, just put it in a clone case.

I find most Vintage Computer parts exchanges to be 100% reversable.

Terry Yager
March 12th, 2007, 06:33 PM
Can we vote for both? Ideally, I'd like to have two of everything...one in pristine condition, and another to soup-up to the max. In practice tho, I've found myself building back down almost everything I've ever hot-rodded, so I s'poze my preference is all original (after playing around with pushing the envelope). (And no, I don't think installing un-original sockets detracts from the item's collectibility).

--T

IBMMuseum
March 12th, 2007, 08:44 PM
...an IBM PS/2 type 8555 that require the replacement of the DS1287 RTC...

You can also rework them: http://www.mcamafia.de/mcapage0/dsrework.htm

NathanAllan
March 12th, 2007, 09:40 PM
I'm gonna vote improvement, but under the condition that it isn't over-improved, such as putting an IDE controller in an XT. It's workable, but not vintage. I would rather replace the shot drive and controller with a good same-era controller and drive. One with a good reputation.

I'm also kinda with Terry, I like to have two similar machines to play with like networking and suchlike.

atari2600a
March 12th, 2007, 09:51 PM
Authenticity: The reason I never attempted an S-Video mod on my Atari 2600.

Druid6900
March 13th, 2007, 06:55 AM
You can also rework them: http://www.mcamafia.de/mcapage0/dsrework.htm

Yes, I've seen that article in several places, but, it's a pretty sloppy hack job. Since I have access to working DS modules, it seems preferable to just un-solder the old ones and replace them. The 8555 is no problem as it's already socketted.

Druid6900
March 13th, 2007, 07:06 AM
I've always gone with the authenticity, personally, leaving socketted chips socketted and the boarded chips without sockets. I've found some collectors are real sticklers about "out of the factory" condition.

If I get a unit in that has been heavily modded (especially prevalent with things like the Tandy Model I), I remove all the non-RS mods, fill the holes, sand it, prime it and repaint the entire case with the original colour. This, of course, depends on the buyer's preference as some of them want them in their "looks used" state.

Hell, I've had requests to make a computer in near mint condition, look 20 years old. A little solvent, a few whacks with a chain and, BINGO, antiques made while you wait LOL.

carlsson
March 13th, 2007, 07:21 AM
Interesting concept, to turn a very fine specimen into average or poor condition. Ideally one should record the process on video and post somewhere.

I agree with Terry. If you own at least one unit in original condition, you may consider turning a second (third, fourth) unit into something extra. As long as it is possible to make it function like the original, it'd be fine with me. Internal memory expansion, improved cooling, perhaps addition of modern interfaces as it is doable. It would not be a computer one collects, but one that you regularly use and show off, in particular if it is a common type of computer.

nige the hippy
March 13th, 2007, 07:40 AM
subtle restoration & sockets is definitely my preference, although if something is definitely beyond repair ....mod away! and have fun with it, much better that than unloved in a landfill site.

dongfeng
March 13th, 2007, 09:20 AM
But surely it really depends on the modification in question? The proposed modification (putting a previously soldered RTC chip in a socket) would be very practical, as in 10 years time it would need replacing again.

I always like my machines in their original style, but would accept a socketed RTC as a very practical (and subtle) upgrade as it would facilitate future repair.

SwedaGuy
March 13th, 2007, 10:00 AM
I usually go for the authenticity route, though I do keep hardware around specifically for "experimenting"--that stuff wasn't "collection quality" to begin with, so no loss if it gets FUBAR...

Even with "authentic" hardware, however, I make exceptions for things like socketing chips for easier replacement. I consider wether or not the manufacturer would have made the modification, in hindsight. If I believe they would have, I will. Does that make sense?

So, to add a socket for a chip that has to be periodically replaced sounds like a worthwhile endeavor, as I think most manufacturers would have approached that part of the design with a socket in mind if they had known that the RTC would not last the life of the machine. If IC sockets were commonly available and established technology at the time, I would say go for it.

Putting an IDE drive in an XT on the other hand, is like installing an ice maker in your dishwasher. It might be fun to make it work, but it certainly couldn't be passed off as original hardware.

For those radical modifications, I guess it come down to this: are you trying to create or maintain a collectors piece, or do you really need that XT to perform a critical function. We have an XT we keep around, because anything in the x86 line more recent than that screws up the Canon basic interpreter. Maybe on day we'll try to give it IDE drives, just for giggles...but I wouldn't even begin to know where to start...

Unknown_K
March 13th, 2007, 12:42 PM
I don't like doing anything that cannot be reversed to stock (no case hacks or funky soldering). I do replace leaky batteries with the coin type and holders but that can be undone.

Most of the machines I get end up with newer/faster HDs, more ram, lots of upgrade cards, and maybe a cpu upgrade.

Brendan
March 13th, 2007, 06:42 PM
Interesting post - this one had me thinking a bit. So long as by upgrading/modifying, the following things occur, I'm almost always up for upgrading:


The system doesn't become less reliable (ideally, it becomes _more_ reliable)
The system doesn't lose any backward compatibility
The upgrade allows me to do something I wouldn't have otherwise been able to, such as:

connect the system to a modern network (hive mentality/data conversion & sharing)
allow the system to act autonomously (RTC upgrades & server functionality)
run an OS or app that I would not have been able to fully take advantage of or run at all



Perhaps all of this stems from the fact that I'm more interested in functionality and getting use out of my systems than preserving "stock" status of any of them. I feel that history isn't well served with a aging broken monument of silicon - 95% of the uniqueness of a machine comes from how it functions.

Upgrades are cool so long as they're not destructive (see my first 2 bullets).

Typically, I do shy away from case modifications, unless it's for the purpose of moving a mainboard into a new one.

I think sockets are absolutely your special friends. System manufacturers never used enough of those or opto-isolators, IMHO.

Just my 2 cents...

Yzzerdd
March 13th, 2007, 07:30 PM
I prefer to improve, while keeping the computer as authentic as possible. I like to use parts the computer was designed for. Hence why I us an ST-251 on my AT&T.

Druid6900
March 13th, 2007, 08:03 PM
Sockets are a blessing and a curse.

They make repair pretty easy, but, on the other hand, they cause a lot of problems as well.

As an example, the Apple III. No fan, to keep it quiet, so Jobs dictated, however, if the chips had have been soldered to the board, the resulting warping of the board wouldn't have affected operation of the unit. As it is, the combination was almost fatal to Apple, especially followed by the Lisa fiasco.

Apples are great to repair, I can pull all the chips, test or substitute them and have it fixed in no time. However, they are cheap, single wipe sockets and they corrode over time and cause all sorts of nasty problems.

Socketting a chip that was replaced for repair, in my opinion, not only removes the authenticity, to a small degree, but, chances of that chip going again are pretty remote. Sockets on board for upgrade options are a must, of course, as de-soldering 8 RAMs or a couple of ROMs, is not going to make it a good sales prospect.

I repair and restore and make available items with the serious collector, for their collection, in mind, so, those are the units that the poll is actually about, not second or third hack machines.

The point about the RTC future replacement is a valid one and I was leaning in that direction, but, I wanted to check it out with the membership before actually doing it. I value the opinions of the regular members here and wanted to know what they were.

IBMMuseum
March 13th, 2007, 08:32 PM
...The point about the RTC future replacement is a valid one and I was leaning in that direction, but, I wanted to check it out with the membership before actually doing it. I value the opinions of the regular members here and wanted to know what they were.

It is important to note that the "Y2K-fixed" Dallas module can't be used in the Model 55SX and other PS/2s. IBM changed the location in CMOS RAM for the "Century Byte" with the PS/2s. But the versions you mentioned should be fine.

Druid6900
March 14th, 2007, 12:04 PM
Ok, so that would mean that the PS/2s have to have the DS1287s as opposed to the DS12887s?

The poll and conversations seem to indicate, by a small margin, so far, that the DS12887s, socketted, are an acceptable deviation from the stock machine and probably wouldn't get anyone's hackles up in the units that don't have a problem with them.

IBMMuseum
March 14th, 2007, 02:12 PM
Ok, so that would mean that the PS/2s have to have the DS1287s as opposed to the DS12887s?

The poll and conversations seem to indicate, by a small margin, so far, that the DS12887s, socketted, are an acceptable deviation from the stock machine and probably wouldn't get anyone's hackles up in the units that don't have a problem with them.

Either the DS1287 or DS12887 (adds 64 more bytes of CMOS RAM), but not the DS12C887. To fix the Y2K bug (actually something that would happen every century with these devices) the DS12C887 module was made to roll over the "Century Byte" location in CMOS. But particular to just the PS/2s, the Century Byte was moved to another location in CMOS when they were designed (meaning it rolls over the wrong location, and has control over that byte location that PS/2s use to track memory size on the system).

Druid6900
March 14th, 2007, 06:02 PM
Ok, thank you for the advice, for future reference.

I was beginning to think just using the original part and socketting them where necessary would be the way to go. Will using the DS12887 (with its extra CMOS RAM) endow these particular machines with any additional benefit?

IBMMuseum
March 14th, 2007, 06:42 PM
Ok, thank you for the advice, for future reference.

I was beginning to think just using the original part and socketting them where necessary would be the way to go. Will using the DS12887 (with its extra CMOS RAM) endow these particular machines with any additional benefit?

The DS12887 doesn't give any extra ability, except that you could use the additional 64 bytes for any purpose you wanted. That is the reason the DS1220 module (battery-backed CMOS RAM) is present on the the 55SX: To hold a disk-less configuration to boot over a network. A 55SX page is at http://www.gilanet.com/OhlandL/8555/8555_Planar.html

The 55SX was believed to be the most heavily-produced PS/2. So successful that Reply made an upgrade planar the IBM based the later Model 53SLC2 on. IBM also had a rare version that soldered in a Cyrix 486SRx2 in place of the 386SX-16.