Forum Rules and Etiquette

Our mission ...

This forum is part of our mission to promote the preservation of vintage computers through education and outreach. (In real life we also run events and have a museum.) We encourage you to join us, participate, share your knowledge, and enjoy.

This forum has been around in this format for over 15 years. These rules and guidelines help us maintain a healthy and active community, and we moderate the forum to keep things on track. Please familiarize yourself with these rules and guidelines.

Rule 1: Remain civil and respectful

There are several hundred people who actively participate here. People come from all different backgrounds and will have different ways of seeing things. You will not agree with everything you read here. Back-and-forth discussions are fine but do not cross the line into rude or disrespectful behavior.

Conduct yourself as you would at any other place where people come together in person to discuss their hobby. If you wouldn't say something to somebody in person, then you probably should not be writing it here.

This should be obvious but, just in case: profanity, threats, slurs against any group (sexual, racial, gender, etc.) will not be tolerated.

Rule 2: Stay close to the original topic being discussed
  • If you are starting a new thread choose a reasonable sub-forum to start your thread. (If you choose incorrectly don't worry, we can fix that.)
  • If you are responding to a thread, stay on topic - the original poster was trying to achieve something. You can always start a new thread instead of potentially "hijacking" an existing thread.

Rule 3: Contribute something meaningful

To put things in engineering terms, we value a high signal to noise ratio. Coming here should not be a waste of time.
  • This is not a chat room. If you are taking less than 30 seconds to make a post then you are probably doing something wrong. A post should be on topic, clear, and contribute something meaningful to the discussion. If people read your posts and feel that their time as been wasted, they will stop reading your posts. Worse yet, they will stop visiting and we'll lose their experience and contributions.
  • Do not bump threads.
  • Do not "necro-post" unless you are following up to a specific person on a specific thread. And even then, that person may have moved on. Just start a new thread for your related topic.
  • Use the Private Message system for posts that are targeted at a specific person.

Rule 4: "PM Sent!" messages (or, how to use the Private Message system)

This forum has a private message feature that we want people to use for messages that are not of general interest to other members.

In short, if you are going to reply to a thread and that reply is targeted to a specific individual and not of interest to anybody else (either now or in the future) then send a private message instead.

Here are some obvious examples of when you should not reply to a thread and use the PM system instead:
  • "PM Sent!": Do not tell the rest of us that you sent a PM ... the forum software will tell the other person that they have a PM waiting.
  • "How much is shipping to ....": This is a very specific and directed question that is not of interest to anybody else.

Why do we have this policy? Sending a "PM Sent!" type message basically wastes everybody else's time by making them having to scroll past a post in a thread that looks to be updated, when the update is not meaningful. And the person you are sending the PM to will be notified by the forum software that they have a message waiting for them. Look up at the top near the right edge where it says 'Notifications' ... if you have a PM waiting, it will tell you there.

Rule 5: Copyright and other legal issues

We are here to discuss vintage computing, so discussing software, books, and other intellectual property that is on-topic is fine. We don't want people using these forums to discuss or enable copyright violations or other things that are against the law; whether you agree with the law or not is irrelevant. Do not use our resources for something that is legally or morally questionable.

Our discussions here generally fall under "fair use." Telling people how to pirate a software title is an example of something that is not allowable here.

Reporting problematic posts

If you see spam, a wildly off-topic post, or something abusive or illegal please report the thread by clicking on the "Report Post" icon. (It looks like an exclamation point in a triangle and it is available under every post.) This send a notification to all of the moderators, so somebody will see it and deal with it.

If you are unsure you may consider sending a private message to a moderator instead.

New user moderation

New users are directly moderated so that we can weed spammers out early. This means that for your first 10 posts you will have some delay before they are seen. We understand this can be disruptive to the flow of conversation and we try to keep up with our new user moderation duties to avoid undue inconvenience. Please do not make duplicate posts, extra posts to bump your post count, or ask the moderators to expedite this process; 10 moderated posts will go by quickly.

New users also have a smaller personal message inbox limit and are rate limited when sending PMs to other users.

Other suggestions
  • Use Google, books, or other definitive sources. There is a lot of information out there.
  • Don't make people guess at what you are trying to say; we are not mind readers. Be clear and concise.
  • Spelling and grammar are not rated, but they do make a post easier to read.
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To V20 or not to V20...

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    Originally posted by voidstar78 View Post
    Re, VGA in the 5150: You're right some early titles don't work with the VGA card.
    Some VGA cards came with a utility program that drastically improved their CGA (and MDA) compatibility. For example, VGA1024.EXE for Western Digital / Paradise VGA chipsets:


      I generally install a V20 in the machines I use frequently. It’s just enough performance increase without being too much (like a full-blown accelerator). I want my PC or XT to still run at a realistic speed, and the V20 is pretty damn perfect for that in my opinion. I’ve never had any compatibility issues with it personally.
      Compaq - It simply works better


        I have a 5150 that I keep in its original condition (8088 CPU, MDA/CGA video, no fixed disk) and a generic Turbo XT clone that gets kitted out with all the extras like a V20 CPU, EGA video, etc. Best of both worlds!


          I don't know if this also applies to the V20, but I clearly remember that once we'd replaced the 8086 CPU in my Dad's Olivetti M24 with a NEC V30, some games started showing certain animations that were disabled before the upgrade. I remember this being the case with Space Quest III and the CGA/Tandy/EGA version of The Secret of Monkey Island. In the latter game, when you walked into the SCUMM Bar™, you would see a pirate swinging back and forth on the chandelier if the game was running on a V30 CPU. Before the upgrade, the chandelier would be hanging still without a pirate in it.

          I'm still not sure whether these games enabled these graphical details on the basis of timing loops, or by checking whether certain 186+ instructions were present. Probably the former.


            well, I have a tandy 1000sx and before I was running an 8088, I could barely run some games (like battle chess for example) I put a D70108C-8 (aka v20-8Mhz and a D8087-1 (aka 8087-10Mhz) and its the best thing I could do to this old box, now I have not found a period game I am not able to play so far. so I am all for the authenticity, but with usability, no one can see the chip and if someone bought it from me, I would provide the original chip for them to downgrade the machine if they so desire.
            TRS-80 MODEL 4, 128K RAM, 360K & 720K, Gotek FDD, FreHD SDCARD HDD, GURU RS232-WIFI MODEM, DWP210
            Eeprom Prog: Inspiron 660s, I5-3330s, with BK-844USB
            Gotek Prog: Dell D520, Dual-Core Intel, 8GB, 500GB HDD, 15" LCD
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              Ah, I forgot about Battle Chess, that was a nice title - my daughter might like that, she's into chess.

              BTW - swapping the chip can change the speed? from 4.77mhz to 8mhz? Just a simple chip swap, no dips or jumpers? Or is it just some efficiency of the chip, makes it effectively like it's running at 8mhz? I just thought the crystal/clock had to be modified somehow, wasn't clear how a chip swap changed the actual rate.
              IBM 5110 ['78], PET 4016 ['80], C64 ['82], IBM PC 5150B ['84]. A retired SysOp, creator of, VUC, ANT


                Originally posted by voidstar78 View Post
                swapping the chip can change the speed? from 4.77mhz to 8mhz?
                No, swapping from an 8088 to a V20 or vice versa does not change the clock speed. The Tandy 1000SX runs at 7.16 MHz.


                  At [here] is an example of a problem that resulted from upgrading an 8088 to a V20.


                    This is a subject that has been discussed in detail by many publications since 1985. The reasons for the V20 running faster than the 8088 at the same clock speed have also been discussed--even in NEC's own literature. Lawsuits by both NEC and Intel on this chip family have also been detailed.
                    Reach me: vcfblackhole _at_ protonmail dot com.