Forum 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.

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.

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.

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.

"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.

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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Cyrix MediaGX build

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    Cyrix MediaGX build

    I was looking into building a Cyrix 5x86 system, but then decided on a Cyrix MediaGX system since this has a Cyrix 5x86 core. I thought this would be a much more interesting build. The biggest obstacle is finding a motherboard. I saw a video on this topic on the CPU Galaxy YouTube channel and he had a link to a seller on eBay. I ordered a motherboard, CPU and accessories. Here are the system specs:

    ECS P5GX-M motherboard
    Geode GXm-266P CPU @2.9v overclocked to 300MHz (Same as a MediaGX just sold by National Semiconductor after buying Cyrix)
    256MB (2x128MB) PC100 SDRAM
    3Com Etherlink III network card
    TopView ET6000 4MB video card
    8GB CompactFlash with a CF to IDE adapter
    1.44MB 3.5" floppy drive
    16x DVD
    Windows 98 SE with Unofficial Service Pack 3

    I opted not to use the onboard video as this made overclocking easier and tighter memory timings. I did end up using the onboard SB16 audio. The next issue to resolve was finding a way to tweak the MediaGX register settings. Thanks to this post on, I was able figure out how to use CTCHIP34 to tweak the MediaGX CPU including enabling Branch Prediciton. I already posted some results in that thread.

    I have CTCHIP34 in my AUTOEXEC.BAT with the following parameters:

    CTCHIP34 cx586 /20:=7
    CTCHIP34 cx586 /0e8:=0f8

    I have no stability issues, Here the results of some DOS benchmarks.

    No tweaks applied:

    Speedsys v4.78 visual results

    3DBench 1.0c - 156.6 FPS
    Chris's 3D Benchmark - 320x200 - 124.3 FPS
    Chris's 3D Benchmark - 640x480 - 35.7 FPS
    PC Player - 320x200 - 48.7 FPS
    PC Player - 640x480 - 19.1 FPS
    Doom - Max Details - 86.54 FPS
    Quake - 320x200 - 35.2 FPS
    Quake - 640x480 - 13.7 FPS
    Norton SI 8.0 = 793.9
    Topbench 40a - 686
    SpeedSys 4.78 CPU Performance Index - 151.09

    Tweaks applied:

    Speedsys v4.78 visual results

    3DBench 1.0c - 162.3 FPS
    Chris's 3D Benchmark - 320x200 - 128.9 FPS
    Chris's 3D Benchmark - 640x480 - 35.7 FPS
    PC Player - 320x200 - 50.2 FPS
    PC Player - 640x480 - 19.7 FPS
    Doom - Max Details - 89.02 FPS
    Quake - 320x200 - 39.8 FPS
    Quake - 640x480 - 15.6 FPS
    Norton SI 8.0 - 1020.6
    Topbench 40a - 690
    SpeedSys 4.78 CPU Peformance Index - 179.82

    Overall this has been a fun build. It's basically like having a 486 system on steroids

    Computer front view

    Windows 98 SE with Cpu-Z info

    Nice build.

    I have one of those AMD 50x15 PICs that has a 400 MHz Geode GX in it and it's basically still a 486 on steroids. I never did try the utility to enable disabled features on it though. As it comes from the factory, it's locked down to Windows CE, you have to use an exploit to get a command prompt and flash a custom unlocked BIOS to it so it can boot other operating systems. Not at all expandable though, the only things you can change are the hard drive and DDR SODIMM memory module.