[QUOTE=Rodrigo2;223357]Luigi,

That's a bummer.

I'll have to investigate whether there is a way to multiboot an ancient machine such as that P75. I just installed a second hard disk on it. If multibooting is possible, I could move all the data files over to the new HDD, defragment the old HDD, and then create a new partition for Linux. What size partition would be needed by the version of Linux that you mention in order to function, and to run Factor_x ?

Rodrigo

P.S. To post this, I had to log in as unregistered and changing my name slightly because every time I logged in to the forum and then tried to reply to your post, I got logged out.[/QUOTE]

On another thought, I'm afraid that Factor is not well suited for a Pentium machine:
- Version 1 used the Giantint all-C library from Richard Crandall, and was rather slow.
- Versions 2 and 3 assumed a huge use of RAM (one structure was 64 MB in size).
- Version 4 used structures of 256KB to best fit in cache, but was not optimized.
- Version 5 executables are TOO optimized for modern processors, and uses the same structures.

So, if you want to use Factor5, you need at least 4 MB of RAM installed. The program footprint is about 140 KB if statically compiled, or 33 KB with dynamic libraries.

If you can install an old version of Linux for i586 machines, you are still at the beginning: you should then:
- Download the GMP library
- Configure the environment with the approriate script.
- Make, make install and make check the GMP (that is, compile it on your machine).
- Download factor5 sources.
- Recompile Factor5 sources.
- Cross your fingers :smile:

I'm sorry I don't have a Pentium machine to avoid all this hassle and let you use an already compiled version of Factor5.

Luigi

[QUOTE=Rodrigo;223397]Wiping the hard drive would mean losing all the software that came pre-installed from Dell, as there were no floppies or Setup files from which to reinstall. I don't want to lose access to that.[/QUOTE]

Get over it. You never had ownership of that software. You simply had a license.

[QUOTE=Rodrigo;223397]Moreover, all my e-mail from that period is in a proprietary format for software that won't run on any of my other PCs, and I do not want to lose access to it. (Yes, the need to access it does still arise once in a while.)[/QUOTE]

Then you should understand that every time you access that system there is a chance it will crash -- and you should try to transfer the data from it to a reliable file system as soon as you can.

[QUOTE=Rodrigo;223397]Finally, and from a psychological viewpoint, I have a chain of PCs dating back to my 1984 Sanyo MBC-555, every one of them still fully functional and in the same state (OS) in which I used them back in their time. It's a pleasure to be able to go back to any of my PCs whenever I wish and recreate the experience of the time. It's a connection to the past. Wiping out WfW3.11 on my P75 would break the chain, and that connection.[/QUOTE]

I resonate with what you say.

I have deep emotional connections with machines going back more than 30 years (my first machine was a TRS-80 Model 1 (Z80 processor)).

But, importantly, I don't have a need to have my old machines around me currently because I've long since backed up the data produced by them...

I can visit my old friends in museums like [URL="http://www.bletchleypark.org.uk/"]Bletchley Park[/URL] knowing that they have done their job well...

[quote=enderak;223287]As far as the saving money aspect is concerned, doing 0.99 units for a year, and then 1.50 units after upgrading will work out to more total work done in the long run. (My 1-year figure is just a wild guess on my part - and this is all assuming you 1) even care about the electricity cost and 2) would put the savings of not running the old machines towards a new one)
[/quote]
enderak,

You're right -- the price of running these old machines is not a big consideration in my case. As it is, two of them are running about half the time anyway for other reasons, so the additional cost of running them 24/7 is not as great as one might think.

[quote=enderak;223287]As far as GIMPS is concerned, the more work the better, regardless of the cost. However, if you hold out the 0.01 units with the goal of adding 0.50 units in the future, it's better for GIMPS in the long run. I'm sure there's a name for this idea, but I'm no economist. :)
[/quote]

The issue that you describe does have a name in economics -- "future value" vs. "present discounted value." :smile:

[quote=enderak;223287]
Of course, if money were no object, you could just keep running the old machines AND buy a new one, and end up with 1.51 units of work being done. ;)[/quote]

Getting a new machine is extremely tempting, and we may well get to that point... although, it wouldn't be because of the savings gained from not running the old PCs. :wink: I would do it (well, at least in part, anyway) to contribute a new multicore machine to GIMPS. Maybe raising that 1.51 figure to 3.51 or somewhere around there...

Rodrigo

[quote=cheesehead;223395]That was probably because you weren't allowing cookies from mersenneforum.org.[/quote]
cheesehead,

Hmmm -- I wasn't doing anything different from any other time. Hadn't changed any settings from the night before. And now again things are fine. <scratching head>

Anyway, as I've said previously, I like the approach you take to the project, but I wouldn't want to become an obstacle for the speed enthusiasts. What would be an out-of-the way range where my senior citizen PC could work for a while, where nobody's likely to come barreling through soon and trip over it?

Thanks!

Rodrigo

[quote=ET_;223403]On another thought, I'm afraid that Factor is not well suited for a Pentium machine:
[...]
I'm sorry I don't have a Pentium machine to avoid all this hassle and let you use an already compiled version of Factor5.
[/quote]
Luigi,

Thanks for getting back to me on this. If not Pentiums, then which processors are your programs optimized for -- later (or earlier) Intel CPUs, or a different brand altogether?

And, is there any other software out there, from anybody else, that would enable this PC to do OBD?

My P75 has 128MB of RAM in it, FWIW.

Rodrigo

[quote=chalsall;223407]Get over it. You never had ownership of that software. You simply had a license.
[/quote]
chalsall,

That's O.K. I still have the USE of that software, but I would lose that if I were to wipe the drive.

[quote=chalsall;223407]Then you should understand that every time you access that system there is a chance it will crash -- and you should try to transfer the data from it to a reliable file system as soon as you can.
[/quote]
Considering that my e-mail is in an oddball format that no other software can untangle, I am indeed resigned to that possibility. What can I say -- I've learned a lot more about computing since 1994!

I suppose I could print out hundreds of pages, but that hardly seems practical. I could also copy the e-mail directories onto floppies, but it would take hundreds of them -- an administrative nightmare, and then there would still be the question of what other PC could read them.

[quote=chalsall;223407]But, importantly, I don't have a need to have my old machines around me currently because I've long since backed up the data produced by them...

I can visit my old friends in museums like [URL="http://www.bletchleypark.org.uk/"][COLOR=#800080]Bletchley Park[/COLOR][/URL] knowing that they have done their job well...[/quote]

That's a nice feeling. :smile:

But let me illustrate my angle on this: Recently my father handed me a quad-density 5.25" floppy that he had just discovered sitting in a box, asking me to find out what was on it. I put the 800K floppy in my MBC-555 and determined that they were family documents and private correspondence that, in light of events many years later, turned out to be quite significant. He decided that he wanted the files, but because (like a lot of people) he had long since donated his old computers, he didn't have any that could read this diskette.

So I put a 360K diskette in the other drive of my old Sanyo and copied the files over because none of my other PCs can read a quad-density.

Next I ported the 360K 5.25" floppies over to my P75 because it has both a 3.5" A: drive and a 5.25" B: drive; and I copied the files from the 5.25" to the 3.5". But my dad doesn't even have a 3.5" drive anywhere in sight.

A home network had not even been conceived of at that point, so the next step was to take the 3.5" minifloppy with the old files to my Windows 98 tower, where I converted them from WordStar (remember it?) to Microsoft Word format. Finally, I copied the files to a USB flash drive and offered my dad the option of getting home delivery of the flash drive, or to receive the files by e-mail. He chose home delivery. :smile:

This project involved three computers that many folks would consider utterly obsolete and useless; and yet under the circumstances they helped me to accomplish an unexpectedly valuable family research purpose. I doubt that Bletchley Park (or an equivalent U.S. institution) would have allowed me free use of their equipment to get this done, never mind the time and expense involved in getting there. Nostalgia aside, I am glad that I kept the old machines around and in working order.

Rodrigo

[QUOTE=Rodrigo;223412]Considering that my e-mail is in an oddball format that no other software can untangle, I am indeed resigned to that possibility. What can I say -- I've learned a lot more about computing since 1994!

I suppose I could print out hundreds of pages, but that hardly seems practical. I could also copy the e-mail directories onto floppies, but it would take hundreds of them -- an administrative nightmare, and then there would still be the question of what other PC could read them.[/QUOTE]What program, there may be a converter available.

[QUOTE=Rodrigo;223412]But let me illustrate my angle on this: <snip>[/QUOTE]
All the more reason, not to mess with them, no? Keep using them as normal, but leave the number-crunching to newer ones.

[quote=Uncwilly;223414]What program, there may be a converter available.[/quote]
Uncwilly,

It's WinCIM 1.4, the CompuServe e-mail software.

I found converters that would go as far back as WinCIM 2.x, but not 1.4, and in any case they offered to convert either to Outlook Express (which to me was virtually unfathomable) or to Outlook 98 (which I never had).

Rodrigo

[quote=axn;223415]All the more reason, not to mess with them, no? Keep using them as normal, but leave the number-crunching to newer ones.[/quote]
axn,

Is there a danger of screwing up a machine, or the OS, with the use of Prime95 or a similar program?

I do know about the "torture test" aspect of Prime95 (in fact, that's how I first heard of GIMPS :smile:), but I don't know that it's possible to mess up a PC irretrievably with it.

Rodrigo

[QUOTE=Rodrigo;223420]Is there a danger of screwing up a machine, or the OS, with the use of Prime95 or a similar program?
[/QUOTE]

Not really, but that was not what I was referring to. I was talking about the attempts to install linux.