You're right, I always (incorrectly) assume that playing Games is all that matters 🤣

But that would making testing such a Cyrix chip even more interesting. E.g. showing which applications scale well and which ones suffer from the smaller bus...

RG100: Time to source one of these Cyrix clock double chips! I know that if you get your hands on one, you will push it to it's limits!

Well this idea is somehow weird, to use a 386/486 combo board to downgrade it to a 386 and then overclock it...
I just see one interesting aspect in this - to test how a 386 performs with VLB.

As for the 386 boards. Usually all chipsets support 33 MHz. For 40 MHz in most cases the identical chipsets were taken and just tested if they run stable at 40 MHz. Thats why there is very often just a 40 MHz sticker attached (on top of the 33 MHz marking).
Like this one f.e.: http://mail.lipsia.de/~enigma/neu/pics/386eteq.jpg
So if you have some standard 386 board, the default rating is 33 MHz.

Tetrium wrote:

AC, you also happen to know about the 386's compatibility with 16meg simms? The manual states it works with 1mb and 4mb simms, but makes no mention of the 16mb simms.

Sorry for the delay, I just noticed that. If you happen to find a motherboard having ALI 1429 chipset, it is almost certain that it will support 16mb simms. Back in 1994 I had a soyo board with that chipset and it was written in the manual that it can have up to 128mb using 16mb simms. And also I have another board with the same chipset, whose manual I was able to find, and while it said it can take up to 32mb using 4mb simms, It worked fine with 16mb simms, but it recognized only the first bank(64mb).

I would think that whether the 16mb SIMMs would be supported might also depend on BIOS support as well. In any case, that ALI 1429 chipset is pretty good for 386 boards. That one, as well as opti 495SLC/495SX. These are all 486 chipsets that also support 386.

TSENG based cards seem to cost a fortune.
🙁

Yeah, but if we start making posts about how crashy those are, lots of BSoD etc, see prices plummet within a month! 😜

And then we buy em clean haha! 😜

All I can hope for is some old lady selling her dead husband's computer equipment.
Does that make me a bad person?

I've bought a couple of Cirrus Logic 5422 cards. Fair price, while they're fast enough, and seem very compatible up to the point I have tested.

TheLazy1 wrote:

All I can hope for is some old lady selling her dead husband's computer equipment.
Does that make me a bad person?

You would be bad, if you hoped that some old lady's husband were to die, in order for her to sell the equipment to you.

However, life's a bitch, and so what would happen in reality is that the old lady in question turns in to one of those mad ebayers, selling her late husband's junk at extortionate prices, using a crappy cell/mobile phone camera to do the photos.

Re: Cyrix clock double chips. Must have one! Must have one! RG100 foams at the mouth!

retro games 100 wrote:

However, life's a bitch, and so what would happen in reality is that the old lady in question turns in to one of those mad ebayers, selling her late husband's junk at extortionate prices, using a crappy cell/mobile phone camera to do the photos.

🤣 Man, I really like your sense of humour 😜

retro games 100 wrote:

TheLazy1 wrote:

However, life's a bitch, and so what would happen in reality is that the old lady in question turns in to one of those mad ebayers, selling her late husband's junk at extortionate prices, using a crappy cell/mobile phone camera to do the photos.

I see we have both been viewing the same auctions...
I know it's rare these days but no one in their right mind is going to pay $180 for an ISA video card.

I see we have both been viewing the same auctions...

It's hard not to view the same auctions, when a huge percentage of the 'vintage computer' type categories are clogged up with hundreds of absurd listings from the same 3 or 4 jackasses. I've been wishing for quite awhile that eBay would implement some sort of seller blocklist, so I wouldn't have to wade through all the crap from 'newsgroups' and 'It Equipment Express' (the guy with the track runner picture on everything) every time I search for something.

Ugh don't get me started on that guy, not only are his prices ridiculous but he only sends express mail so his postage is daylight robbery as well.

One suggestion is to use the ebay.com site instead of your own country's ebay site, I find a lot of things come up that don't otherwise and you can sometimes find a decent bargain that doesn't cost a lot for postage.

1) Factory fitted QS8888 20ns speed chip replaced with a 15ns chip.
2) Factory fitted 15ns tag chip left alone.
3) Factory fitted 20ns cache chips replaced with 15ns chips.
4) Factory fitted 80MHz oscillator replaced with a 100MHz unit.
5) Jumper set to "obey the speed at jumper location 6".
6) Jumpers set to "maxiumum speed". This is /4. This means osci/4 = bus speed. That means 100/4 = 25MHz.
7) Gold plated 4MB 70ns SIMMs. Total 16MB.
8 ) Jaton (c) 1992 AMD 386DX-40. Due to the 100MHz osci, this runs at 50MHz.
9) SB Pro 2, model CT1600. Works at max speed, but only in DOS. In Windows 95 at max speed, it fails to function.
10) EIDE IO controller.
11) Cirrus Logic ISA VGA card. Works at max speed, in both DOS and Windows 95. Generally speaking however, it's a slow card compared to others eg Tseng, etc.

When the mobo is set to max speed, sometimes it doesn't work. It seems a bit "hit and miss". If I drop the bus speed down to /6, then it always works.

I also tested some ceramic Intel 386DX-33 chips. I found them more difficult to remove from the mobo, compared to the Jaton AMD 386DX-40 chip as seen in the photo above. When I removed one of these Intel chips, a piece of ceramic material broke off from the corner of the CPU. I retested it, and it still worked.

DonutKing wrote:

Ugh don't get me started on that guy, not only are his prices ridiculous but he only sends express mail so his postage is daylight robbery as well.

One suggestion is to use the ebay.com site instead of your own country's ebay site, I find a lot of things come up that don't otherwise and you can sometimes find a decent bargain that doesn't cost a lot for postage.

Actually I find the ebay search function to be unbelievably incompetent at times...or maybe it's just ebay.
I find some random sellers sale and click what other items he has for sale, and it will come up with ZERO sales! I'll refresh the sale he has and it'll still be there.

Finding a sale of some interesting piece of hardware, then doing a search and the search doesn't come up with the page you already found, even though you copy+paste the sales name!

ebay.com not having a "Sort:lowest first" option so I'll need to wade through the moneygrabber's sales first before reaching the normal auctions -_- (and yes, I know ebay removed this option for reasons I don't personally care about and yes, but no, I don't want to enter the "lowest+shipping" option as it skews the results I wanna see).

Speaking of ebay, what about the error in their search engine for "OR" searches. A while ago, I discovered that if you had a search that did this:

(x,y)

It would not work if ebay "cleverly" and automatically substituted one of your "OR" search items, if ebay believed that one of these search items was also popularly listed on ebay as some other piece of text. This "clever" substitution made your (x,y) "OR" search fail. I had to redo all of my carefully thought out "OR" saved searches because of that bug. Here's an example:

(widget_x,widget_y)

If ebay thinks that the word widget_y is the same kind of thing as widget_z, your "OR" search fails. An "OR" search uses this format: (x,y). The way around this bug is to look at your "OR" saved searches, and if you believe that ebay is cleverly substituting either one or the other word, then you have to "break up" your "OR" search, and do 2 seperate searches, like this:

widget_x
widget_y

DonutKing wrote:

I haven't pulled my system apart yet to try out some lower latency SIMMs, that's probably the first thing I will try.

I can save you this trouble! I have just tested the Contaq 386 mobo with identical SIMMs as seen in your O.P. The Toshiba "slow as slugs" 100ns 9 chip stuff. It makes no difference at all to my Speedsys results. I can boot up this thing at max bus speed (20 MHz), using an 80MHz osci, with a Diamond Speedstar64 ISA VGA card. I get 9.29 in Speedsys. The one difference between this test rig and yours is that I could only find 4 SIMMs, and you were using 8. Of course, other differences exist, such as you are using a Maths Co-Pro, and other add-in cards.

OK cool, thanks for that, saves me a lot of effort 😁

I suspected that would be the case. My understanding is that with identical bus speeds and wait states, RAM with a lower NS rating won't increase performance.

I think you just got a freakishly good motherboard 😀

DonutKing wrote:

I think you just got a freakishly good motherboard 😀

Very unfortunately, from your perspective, I disagree. I don't think there's anything special about my mobo. The reason I think this is because I bought a bunch of them, and I've spent several weeks messing about with them, and they all perform well.

I think there's something odd about your set up. It could be the add-in items you have that I don't have, eg Math co-pro, and/or other add-in cards. There's also a horrible thought that it could be something odd about your CPU. You got it from the same seller who sold me those "chopped up" CPUs. Could it be perhaps that this CPU is not a genuine 386DX-40 in some way shape or form?

I bought some 15ns cache chips recently. They are made by UMC. I put 9 of them (256Kb) in to the mobo, and this hot rodded beast of a board boots up with a 100 MHz osci at top bus speed. Although I can't beat my previous 10.17 score in Speedsys, I did get 18.8 in 3DBench, which beat my previous best score of 18.6. I am now using a 1MB (soon to be upgraded to 2MB) Diamond Speedstar64 VGA card.

Yesterday, while I was using my 386, I thought to set the bus speed to 20MHz, to see if windows (I'm running version 3.11) were going to run any faster. As I knew already, the vga and the hd controller didn't have any problems with the 20 MHz setting. But unfortunately I can't say say the same thing about the SB AWE32 I use on that... I doesn't work at all. Which makes me think, that in the end it's not worth trying to make the 386 perform the fastest possible... For me it's only about compatibility and durability from now on, rather than maximum performance.
btw, I think I need to try another hd controller, as I cannot use the "32 bit disk access" option. If I enable it, I get blue screens and it hangs. And it's a bit slow..... it takes about 12-13 secs to load windows. I'm thinking that I shoould use 4 x 4MB simms instead of 8 x 1MB ones.
Perhaps I wouldn't say that if I hadn't tried windows 3.11 on my pentium, which takes just 2-3 seconds to load.....