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68882 FPU, worth the upgrade? And other upgrades.

Flan

6502
Hello all!

I've got an LC520 with a 32Mb stick of RAM (total of 36mb overall with the 4mb onboard) and a 1GB hard drive. I've also got an ethernet card in the expansion slot.

So the floppy drive has never worked since I purchased it, and the SCSI internal CD drive has finally bitten the dust... by the smell of it, something died inside that CD drive.

But I digress, I'm looking to hopefully get some replacement drives for this LC (since all the SCSI CD drives don't fit because apple put the 4 pin molex power connector upside down and on the wrong side of the SCSI port whyy)

I'm also contemplating getting an external SCSI zip drive ( do those exist? ) which I would assume would make transfers easier.

Since I'm in the market for drives, I figured maybe I ought to pick up some other accessories or upgrades that it could use.

The first thing that came into mind was a 68882 FPU since my unit doesn't have one. As I've never really experienced it, I'm curious as to how significant of a performance difference adding an FPU would make, if any at all. If it's really insignificant I might not bother unless I can pick it up for a few dollars.

And on that note, are there any other upgrades I should look for or anything significant? I read something about a Sonnet card that would bring me from a 68030 to a 68040, but I would assume that those aren't worth the ridiculously high asking prices.

Anything worthwhile for the expansion slot? I wouldnt mind replacing / (complimenting?) the ethernet card, and besides, the 520 is super easy to work on so I'd have no problem with just swapping between two expansions as needed.

***Also,*** before anyone says anything-

No I don't have a CC I'm not swapping boards

No I'm not overclocking it; unless I stumble upon a 550 in which case the over clocking is already done for me.

One other thing, and I already know what the response will be, but I'd like a little input on this as well; I haven't recapped the board in this guy. Now, I've had no problems with this Lc520, it's run fine, there's no signs of bulging or leaking or anything like that. I've also put a brand new, fresh clock battery in it about a year or two ago.

I'm hesitant to begin a recap process because I'm terrible with that sort of thing and last time I tried recapping something.. well... let's just say that computer is no longer with us (it was a wintel pentium iii don't worry) besides, I'm thinking that it runs fine assume to and there's no sign of any damage on the board so.. is it safe to keep running it until I notice something? I know the best/smartest thing to do would be a preemptive recap but... thoughts..?

Also, I'd like to think the battery is safe bc it's new but I'd assume you guys know better than I so I figured I'd bring it up.

This post has become a rambling mess but whatever. Upgrades! Drives, expansions! What should I do?

Haha

Anyway, Preemptively thanks!

 
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My sincerest apologies, for typos and edits, I'm trying to fix things, it's late and I'm not quite awake right now haha

 
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It's my understanding that dead or dying capacitors often smell like dead or dying fish; this might explain your dead or dying cd drive.

External SCSI zip drives do exist, and show up various places from time to time.  It is a handy sneaker-net sort of way of transferring data.  Also, they're bootable, which can be super handy.

I haven't seen FPUs being very useful in the older machines except for some software that takes advantage of it.

 
Unless the software you're running actually uses the FPU, you probably wont see any difference.

You'd be best comparing a 68040 vs a 68LC040, that would pretty much give you an idea as the only difference between he two is the FPU.

I just look at the price, I was genuinely surprised at how much those cost.. If you want a fully maxed machine and to say it has an FPU go for it.

 
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Okay, going in order here;

The drives: The floppy drive may be a fairly easy repair. There is a great guide on this site (in the wiki?) on how to do maintenance on the 800k and 1.4mb drive (your LC). Especially if your drive can still eject the disks, it may just need cleaning and lubrication.

I'm not sure about the CD-ROM. You can try dismantling it and VERY carefully clean the laser lense with a qtip and rubbing alcohol. It worked for my external SCSI CD-ROM. Or better yet a special cleaning disk. Maybe someone else has more info on your particular CD-ROM. Given the smell, i agree you may have some spent caps in there.

External SCSI Zip drives are amazing :) If you happen upon one, buy it and some disks. The 100mb version works well with every SCSI Mac. Not sure about the 250mb version.

I put the 68882 FPU in my 520 because some games can take advantage of it. I think things like StuffIt may be able to as well, but can't recall.

No idea about the 040 upgrade card.

Aside from the Ethernet card, the Apple IIe emulator card and the PC video card(allowed adding an external monitor for extended desktop) are two of the most common cards.

I know you aren't overclocking, but there is an incredibly easy way to get the CPU from 25mhz to 33mhz (essentially going from a 520 to 550. It involves removing 3 resisters, but is fairly easy and doable.

As for the capacitors, I haven't done mine yet. That said, I plan to in 2017, either myself or through one of the members here or maccaps/uniserver. The thing is, it will probably work fine until it doesn't. And when it doesn't, hopefully it's only because the capacitor is no longer putting out the correct voltage and not because the leak has eaten through a trace. It's very possible they could be leaking as we speak directly underneath themselves and just haven't spread yet. Or maybe they are all fine and good for a few years. It's really hard to tell. If you aren't confident then I wouldn't blame you for outsourcing that project. I definitely didn't do my own SE/30 because I didn't trust myself to not screw it up :)

Finally, the battery. If it is new, I'd say check the voltage on it every year or so. They start at 3.6volts. I'm not sure of the minimum threshold before they stop working, but if I see one under 2.0volts I'll just toss it out. That's erroring on the side of extreme caution. Remember that most of the exploded batteries probably sat flat dead, or barely above 0, for a decade or more before exploding. If you use it daily, check every year. If putting the computer into storage for any extended time remove it. :)

 
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