Announcement

Collapse

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.
See more
See less

386 performance ceiling?

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

    386 performance ceiling?

    OK now, I've thrown everything I could to my 386 PC. It is now like:

    CPU: 80386DX-40 (AMD) / 80387DX (IIT3C87-40)
    Mainboard: 4386-VC-HD ( http://stason.org/TULARC/pc/motherbo...386-VC-HD.html )
    Cache: 128K L2 cache
    RAM: 32 MB RAM 60ns non-parity ECC
    Video card: Tseng Labs ET4000 W32, or S3 928

    As you can see, everything is the most advanced I can fit in, apart from the cache, where I tried to add another 128K (from a 486 board) but couldn't get a stable system. The PC still gets its ass handed to it performance wise, compared to a Pentium 133MHz, S3 Trio 64V+ card, 70ns RAM that I have. I was hoping that all these upgrades would somehow bridge the gap, but I guess I was wrong, as the performance difference is still so big that it is obvious without even the need to run a benchmark suit.

    #2
    May just be wishful thinking. I'm not sure what you were doing to hope it'd compete with a Pentium. Honestly even 486 to Pentium was a nice performance increase. There are lots of internal tweaks with the opcode timing, predictive commands (at least in the K6-2 world) and other tricks that came out it'd be kinda hard to keep up with the new beasts in town.

    You could certainly benchmark it against your other changes though and see what makes the biggest improvements. I'm sure your 386 is pretty damn sweet compared to others though.
    Looking to acquire: IBM 5100, Altair 8800

    Comment


      #3
      I'm not sure what you expected, comparing a 386 to a Pentium. My architecture is a bit hazy, but I'm pretty sure the 486 and moreso the Pentium benefit greatly from pipe-lining, which is going to give any chip a large advantage.

      Comment


        #4
        In other news, no matter how many upgrades I add to my Pentium 3, it is just smoked by my Core 2 Duo...

        Yeah, 386-to-Pentium is such a huge jump, you're not going to make up ground. The only way you could POSSIBLY get a 386 to be faster would be to purposefully hobble the Pentium. (Pentium 60, slow ISA video card, etc.)

        Not to mention, you're using a video chip on your 386 that was designed for a 32-bit local bus (VESA, EISA, PCI,) it might even have its performance HINDERED by being used on an ISA card. Might be better off to get a fast designed-for-ISA chip.
        Apple ][+ through Retina MacBook Pro, 5150 PC through Core i7 8870/GeForce GTX 1080Ti and quad Itanium 9150M, and many in between.
        Newton, Palm 1000, Palm V, N-Gage, Tapwave Zodiac, iPhone, iPhone X.
        Intellivision, Game Boy through 3DS, Wii, XBone

        Comment


          #5
          Yeah, there seem to be many speed critical differences. Integrated L1 cache, integrated FPU, higher instructions per cycle and the ISA bottleneck as well (although I'm not sure how much of a bottleneck ISA is, as I might be CPU limited). I got rather used to modern CPU development rythms (only 10-30% faster every next gen) and forgot that those times, 2 generations can have an entire 10x performance gap. Well, anyway, this 386 will do fine for my vintage collection as it now is. But maybe I'll need something better for an ultimate DOS/Windows 3.11 platform

          Comment


            #6
            Well, to be fair, your motherboard is an ISA-only model, so bandwidth to peripherals is rather limited. Also remember that the 80386 was a very ambitious chip for the time, being Intel's first 32-bit x86 chip.

            Appreciate it for what it is.
            Reach me: vcfblackhole _at_ protonmail dot com.

            Comment


              #7
              In my own testing I've found that a 386DX40, with 256KB cache and ET4000AX is about equivalent to a 25MHz 486 with equal cache and a Trident ISA video card.
              386 pulls ahead slightly in some games, the 486 is better in others.
              The 486 tends to be better in benchmarks though, but both machines feel pretty close in real world usage.

              If I put the ET4000 in the 486 I find its generally the better machine for gaming.

              I also tested an Intel 486DX4-100 against a socket 4 Pentium 60 with the same PCI S3 video card and, similar to the results above, I found that these two systems were fairly close as well. (obviously in FPU intensive stuff like Quake the pentium is significantly faster). Even in a Doom timedemo the 486 was slightly faster than the Pentium.

              So to extrapolate these very unscientific results, you'd need a 320MHz 386DX to even think about holding a candle to a 133MHz Pentium.
              The 386's lack of PCI will hinder it even more in disk and video intensive tasks (if you can find one of the seemingly rare 386 boards with VLB then this might bridge the gap a little bit, but not totally).

              In fact, have a look at this chart:
              http://www.pcguide.com/ref/cpu/arch/...ecifics-c.html

              You can see that in the benchmarks used, the Pentium 133 is about 10 times faster than the 386DX40. Admittedly they are synthetic CPU benchmarks but they give you an idea of what's going on.

              so, yeah, I think you might have been dreaming if you expected your 386 to put up a fight against a Pentium :P

              Comment


                #8
                But remember, at one time, the 80386 was at the heart of a supercomputer.

                http://www.qq22.net/qq22/comp/pages/s81.html
                Reach me: vcfblackhole _at_ protonmail dot com.

                Comment


                  #9
                  The 386-40 was 1991 if memory serves me, and the Pentium 133 came around mid 1995. Its like comparing a late Pentium 4 to an i7. I LOVE my little 386. It works great for pre-pentium dos games. And if i want to run something newer I have a Pentium pro system. (not to mention a 486 build in progress) I have a computer for every major generation of processors. While its not an elegant solution, I do love collecting and assembling the computers, almost more so than actually using them!
                  It is a mistake to think you can solve any major problems just with potatoes.

                  Comment


                    #10
                    As stated a 386/40 is about the same as a 486 DX/25 (mostly because of the slow 25mhz bus on the 486 vs 40 for the 386). It took an overclocked 486/133 (to 166) to get into speed of the first Pentium chips, or a Cyrix 5x120 or so which was a Pentium era chip stuffed into a 486 socket.
                    What I collect: 68K/Early PPC Mac, DOS/Win 3.1 era machines, Amiga/ST, C64/128
                    Nubus/ISA/VLB/MCA/EISA cards of all types
                    Boxed apps and games for the above systems
                    Analog video capture cards/software and complete systems

                    Comment


                      #11
                      What about swaping the 386 for a 486dlc? Should nearly double performance.

                      My 386 rig just broke - need to find and repair the trace for the keyboard
                      386 vlb motherboard with 256k 15ns cache
                      Ti486 dlc (8kb l1 cache) clock doubled to 80mhz
                      Cyrix 3/487 mat copro
                      32mb 60ns ram
                      Vlb caching ide controller
                      Vlb 4mb 64bit vram

                      The machine runs win95 really well!

                      Comment


                        #12
                        By cheating I was able to get my 386 almost to the level of a DX4-100 (minus FPU). It involved using IBM DLC3-100 chip with 16kb internal cache. It is technically a 386 chip on steroids. Of course you'll still need a 386 board with VLB slots if you want decent graphics performance.
                        "Will the Highways on the internets become more few?"

                        V'Ger XT

                        Comment


                          #13
                          You can speed up the CPU by using a 486 class upgrade but that only works well for small programs that are CPU intensive. Once you start hitting the ISA bus for video, sound, HD data, massive RAM swapping, etc the whole system will show its age.
                          What I collect: 68K/Early PPC Mac, DOS/Win 3.1 era machines, Amiga/ST, C64/128
                          Nubus/ISA/VLB/MCA/EISA cards of all types
                          Boxed apps and games for the above systems
                          Analog video capture cards/software and complete systems

                          Comment


                            #14
                            I pulled some 3d benchmarks with the DOS 3dbench. The results seemed pretty sensitive on the cache memory timings, so I might try to find a way to stabilize 256K cache in turbo mode:

                            ET4000W32/no cache: 8,4
                            ET4000W32/128K normal timing cache: 13
                            ET4000W32/128K fast timing cache: 14,2
                            ET4000W32/128K turbo timing cache (memtest86 fails): 14,4
                            ET4000W32/128K fast timing cache/FPU removed: 14,2
                            MXIC(old cheap vid card)/128K fast timing cache: 13,5

                            Comparing to others results here: http://imageshack.us/photo/my-images...rkdatabas.png/ ,the performance is OK, but could be better. VLB 386 systems don't have a significant performance increase, according to these numbers.

                            Comment


                              #15
                              VLB 386 don't benefit from VLB with a regular 386 chip. But I noticed a pretty huge performance increase with the IBM DLC chip.
                              "Will the Highways on the internets become more few?"

                              V'Ger XT

                              Comment

                              Working...
                              X