Wanted Cyrix 386->486 upgrade kit for GoldenGate and other

tiim

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Hi there,

Do not get the Cyrix chip for your bridgeboard (C= or Vortex). Get the TI 486 SLC2 50 Mhz. The difference is the Cyrix has a 1k cache and the TI has 8k, performance difference is significantly increased.

There is a seller on eBay who has them. You will need to solder the chip directly to the board. There are a few AmiBayers who can do this for you if you don't have the tools.

Run the chip only with hestsink/fan as it will get got. Chip is 5v tolerant, but the core is 3.3v resulting in higher temperature.

Cheers,

Tim
 

RetroPanic

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Hi there,

Do not get the Cyrix chip for your bridgeboard (C= or Vortex). Get the TI 486 SLC2 50 Mhz. The difference is the Cyrix has a 1k cache and the TI has 8k, performance difference is significantly increased.

There is a seller on eBay who has them. You will need to solder the chip directly to the board. There are a few AmiBayers who can do this for you if you don't have the tools.

Run the chip only with hestsink/fan as it will get got. Chip is 5v tolerant, but the core is 3.3v resulting in higher temperature.

Cheers,

Tim
Hi Tim
Thanks for the hint. Doesn’t run with 50mhz even the board is a vortex slc not slc2 ?
Sounds good to me, my you have the Name of that eBay seller ?
Cheers
Rolf
 

keropi

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I would be careful with the TI486SXLC2-G50-PQ cpus, they only seem to be 5v tolerant for I/O but still need 3.3v for core
ofcourse I do not know if this has been done before with the goldengate - so maybe nothing to worry about

also like tiim mentions do not bother with the cyrix chips, they only offer benchmark improvements but real-life performance is almost the same - 1kb L1 cache is too small

there is some info about voltages here: https://www.cpu-world.com/CPUs/80386/Texas Instruments-TI486SXLC2-G50-PQ.html

 

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trixster

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I’ve been running a Ti486SXLC on a goldengate for many years, no problems. Needs cooling.
 

Xanxi

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The 5V story is bullshit as we have discussed on other threads. It has refrained some of us to upgrade for 10 years but it works no problem on A,2386 and GG as well.
About the Cyrix chip with 1KB, i wouldn't say as Keropi said. The Cyrix 486SLC2 is a vast improvement over the 386sx and the larger cache of the TI chip is only a bit more.
I have brigdeboards with both chips.
For historical reasons, i prefer to use my A2386 with Cyrix to match my nice Cyrix upgrade sticker on the right side of my A4000 case and because i used this board and CPU for a very long time.
In benchmarks (Norton), the 386sx25 is about 18, the Cyrix 486SLC2/50 is about 67, the TI chip is about 71, both more or less on par with a 486DX33 as a CPU but of course not as whole system because of 16 bits bus limitations. Only Doom seems to improve a bit with the TI chip, but is still slower than Doom on the Amiga (DoomAttack) which flies with a 68060.
Most of the games playable with the bridgeboards (Lucas, Sierra, Prince of Persia 1/2, RPG, Alone, Wolf3D, etc) feel almost the same on the 386sx of the 486SLC2 because the bus is still 16 bits.
If you are interested in the conveniency of plugging the clip-on Cyrix upgrade without soldering, i might still have one in my storage, but replacing the CPU is better to avoid bad contacts.
 

keropi

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Well from what I saw it is only a vast improvement in benchmarks where the 1kb cache gives the impression of a faster cpu.
But on real-life performance maybe you get +0.3 fps in Wolf3D and that's about it. 1kb of cache is so ridiculous amount that it almost gives the impression it was added just to achieve better benchmark scores :ROFLMAO:

*MAYBE* if you have a properly designed motherboard for the 486SLC there would be a bigger improvement because of proper bios support and cache strategies but I am also not thinking it would be that significant.
At least that is my experience with various SLC systems and upgrades I have (excluding the IBM 486slc that is a different core and can rival a 486DX2/66 even with a 16bit bus). The only thing that would really help these SX/SLC systems would be L2 cache which is very uncommon to be implemented in them...

Nonetheless it is good to know that at least on amiga bridgeboards you can just replace the cpu - on pc world the discussions are inconclusive: some say it worked fine some say it does not - probably motherboard dependent.
 
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trixster

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The first part is not true, at least in my experience of having had both the Cyrix and Ti processors on my GG at some point. The difference in peformance between the Cyrix and Ti for memory intensive games such as doom is significant. Pair that cpu with a fast frame buffer vga card like an ET4000 and a highly optimised version of Doom like FastDoom and you suddenly have a credible performer.
 

tiim

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I am using an ISA bus clock-doubling VGA card, the Diamond Speedstar Pro to push VGA games along. I do not have benchmarking results between C= bridgeboards with the Cyrix vs TI chips, but there are two good reasons to go with the TI. The first is availability. They pop up on eBay often, whereas I haven't seen Cyrix for a while. Second, more cache can't be worse than less. Even a 5% speed boost is worth it when you consider what you are stuck working with, and how much cash you doled out to get there.

Either chip is better than the stock i386SX for sure. In fact, the Vortex 486 was a Cyrix part from the factory.

These two chips aren't the only ones out there. Have a look on the following site, it is well organized, and will help you get the most out of a bridgeboard (CPU information also pertains to GoldenGate):

In the end, you have a pretty basic PC that would be frustrating to run Windows 95 on. (Vortex might win here with 16MB) Windows 3.11 seems to run fine. The PC side will never be as fast as a similarly equipped PC anyway, and there are kludges with peripherals, (Floppy, KB, Mouse, 500MB HDD bios limit) I/O address settings, etc. you really get down to details when using one of these boards. It's more a labor of love and curiosity.

I use a 5v Raspberry pi heatsink/fan, and have run the board continuously all day for weeks now.
 
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