Which 5x86 CPU? AMD or Cyrix? The AMD and Cyrix chips run at 3.45v, so you'll need a board that can handle voltage.

The Asus PVI-486SP3

Good things.

With the latest BIOS you can run all socket-3 CPUs (3.xx BIOS versions won't work with all BIOS chips, replace the BIOS-chip if it's too old)
Working PS/2 mouse header!
VLB + PCI
Well documented
Good quality
Good layout
Good CPU, memory and cache performance

Less good stuff.

Not the best video performance, especially with PCI video-cards (~10% slower than the fastest boards).
Maximum amount of cache is 512KB and you need 4x "128k x 8" chips to get more than 256KB (~$15 on Ebay).

This is in my opinion the best 486 board out of the 15 or so I own so the Asus PVI-486SP3 is what I would use.

Skyscraper wrote:

The Asus PVI-486SP3 […]
Show full quote

The Asus PVI-486SP3

Good things.

With the latest BIOS you can run all socket-3 CPUs (3.xx BIOS versions won't work with all BIOS chips, replace the BIOS-chip if it's too old)
Working PS/2 mouse header!
VLB + PCI
Well documented
Good quality
Good layout
Good CPU, memory and cache performance

Less good stuff.

Not the best video performance, especially with PCI video-cards (~10% slower than the fastest boards).
Maximum amount of cache is 512KB and you need 4x "128k x 8" chips to get more than 256KB (~$15 on Ebay).

This is in my opinion the best 486 board out of the 15 or so I own so the Asus PVI-486SP3 is what I would use.

Then again, more than 256k of L2 cache on a 486 is really not that well needed.

Ampera wrote:

Then again, more than 256k of L2 cache on a 486 is really not that well needed.

Yea I agree, I use 256KB cache with 2x16MB memory and even Windows 95 is very snappy.

Winbond W29EE011 is the flash chip I used to flash the latest BIOS for the Asus PVI-486SP3. It's not one of the two listed supported flash chip models but works perfectly and it's easy to find on Ebay for a dollar or two.

I have now am4x86 120mhz AMD
Im thinkin to upgrade later to amd 5x86 or so

Have ordered sst29ee chip for flashing. Tried 27c1001 and that was no post, will the pvi-486sp3 post without backup battery? The aka "coin cell" ?

riku wrote:

I have now am4x86 120mhz AMD
Im thinkin to upgrade later to amd 5x86 or so

Have ordered sst29ee chip for flashing. Tried 27c1001 and that was no post, will the pvi-486sp3 post without backup battery? The aka "coin cell" ?

I would thnk it would post without a coin cell.

As long as the sst29ee is a 128K x 8 (1 Mbit) chip with 5V programmng voltage it should support the latest BIOS. Be sure to remember to jumper the motherboard for 5V BIOS programming voltage if your old flash chip was one with 12V programming voltage. TH99 lists the jumper settings for BIOS programming voltage, the manual does not.

Ampera wrote:

Skyscraper wrote:

The Asus PVI-486SP3 […]
Show full quote

The Asus PVI-486SP3

Good things.

With the latest BIOS you can run all socket-3 CPUs (3.xx BIOS versions won't work with all BIOS chips, replace the BIOS-chip if it's too old)
Working PS/2 mouse header!
VLB + PCI
Well documented
Good quality
Good layout
Good CPU, memory and cache performance

Less good stuff.

Not the best video performance, especially with PCI video-cards (~10% slower than the fastest boards).
Maximum amount of cache is 512KB and you need 4x "128k x 8" chips to get more than 256KB (~$15 on Ebay).

This is in my opinion the best 486 board out of the 15 or so I own so the Asus PVI-486SP3 is what I would use.

Then again, more than 256k of L2 cache on a 486 is really not that well needed.

Why not? If motherboard supports more and you have the correct chips, go ahead 😀

kixs wrote:

Ampera wrote:

Then again, more than 256k of L2 cache on a 486 is really not that well needed.

Why not? If motherboard supports more and you have the correct chips, go ahead 😀

Wth the Asus PVI-486SP3 using 4x "128k x 8" chips might actually not be faster than using 8x "32k x 8" chips. I think I have seen some tests showng that 8x "32k x 8" cache chips for some reason wins out over 4x "64k x 8" cache chips so the benefit of having twice the amount of cache could be negated by using only 4 chips. I guess this could differ from board to board.

The Asus PVI-486SP3 do sadly only have 4 DIP 32 sockets and 4 DIP 28 sockets so using 8x "64k x 8" or 8x "128k x 8" chips isn't an option.

If someone is going to use NT4 then upgrading to 512KB cache is more important to get 64MB memory fully "writeback" cached.

With motherboards that have 8x DIP 32 sockets upgradng to 512KB cache is a no-brainer as "64k x 8" chips are cheap and more easy to come by. 😀

Some of the 486 boards with fake cache actually perform pretty well and are very functional due to the chipsets being used. I have no complains with my faketastic 80486 VIP

the performance of fake cache board is very good, its fast. but again reason why i found the fake cache thing was GUS not working. so there is something going on.. it has sis chipset and it is ok. ofc now i find out about fake cache i going to switch it.

I managed to find out my eprommer programmer wont support 1M chips, thats is reason i could not get 27c1001 working. i think it should work like flash. but it is write protected. Wednesday i going to borrow a bigger prommer if that has support. while waiting those 1meg 29EE flashes going to try normal proms.

EDIT:
i rip out 29EE010 from an old non working pentium board. again my prommer will prom it but well not as suppose... it will erase it, and prom random stuffo on it, but not as it suppose 🙁

Heureka!
After numerous tries of proms etc this one needed at least 20 times reprogram, but finally
Then not started... started to change cpus and it seems amd 66 was the heureka one, with intel was no luck, maybe jumper setting... i got finally picture!!
Have no idea if mobo is ok need to test it out later today:) but im so happy all efford pay back now 😀 😀
Bios is 306 as i readed 307 has problems

EDIT SORRY OF PIC Wrong way, i just posted with mobile phone fast, clicking it will display correct orientation.

put a 3volt CPU in then jumpered according manual then regulator smoked 🤣??
searched google came this post: Best PCI performance... okey it seems need find a transistor now. it is a pnp one. anyone else hving issues installing 3volt cpu on this board?

Got the board working again, now with right cpu.
thanks again all for help

More repair pictures here: https://pilvi.titanix.net/apps/gallery/ ... ETROSETUP)
also installed 256kb of cache, dunno if i should keep that or go 512? i have 64M of ram, but it is possible to decrease to 32M.. have windows95 and old dos games, its plenty for it

there is the mosfet switch replace with IRF: (was the switch, not the pnp transistor what acts like a regu)

anyone knows are this ram modules FPM ??

Need some tips about installing graphic card, should i just go with PCI s3 trio 64v+ or put a VLB one?

More pictures on graphic cards here:
https://pilvi.titanix.net/apps/gallery/s/Iude … tteja%2FVLB_GPU

-

The SIMM looks like a 32MB one, the part number suggests it's FPM. Just google the part number (sorry I'm a bit lazy atm), but you could also just try them in your board.

Or try in an old Pentium board that works with EDO. It should display whether it's EDO or FPM.

This might be a nice site to read up on the SIMMs http://www.chipmunk.nl/DRAM/DRAM.htm

riku wrote:

Got the board working again, now with right cpu. thanks again all for help […]
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Got the board working again, now with right cpu.
thanks again all for help

also installed 256kb of cache, dunno if i should keep that or go 512? i have 64M of ram, but it is possible to decrease to 32M.. have windows95 and old dos games, its plenty for it

Need some tips about installing graphic card, should i just go with PCI s3 trio 64v+ or put a VLB one?

With 256KB cache 32MB memory is best because then you can run the L2 cache in Write Back mode and still have all memory cached. 32MB is enough for the kind of Windows 95 games that run well on a fast 486.

The Asus PVI-486SP3 is probably a little bit faster with a VLB card, I think your Western Digital card would be really fast. I'm also using Windows 95 with my Asus PVI-486SP3 system but I'm using a Matrox Millenium II 4MB PCI card to get good picture quality at 1024*768 in Windows. For me picture quality is more important than getting the small performance increase a fast VLB card provides over a PCI card with this motherboard.

thanks for the answer, it is unsure if it fpm, i tried google. thats i asked here. it is yes 32M one.
i do have a pentium board under test, but that one is not showing if it edo or not.
I removed other 32M, so pc has one simm of 32M. after little struggling i got cache + cpu WRITE-BACK Working!!! it needed to do odd things, jumpers and change cache rams. so 32M is maximum cacheable memory, so i removed other simm.
would be nice if someone has more optimal settings? 😀

Anyone please could point me to where i can get 1024 cache modules cheap? if i upgrade to 512k, then i can use 64M

About VLB card, i have wester digital (untested) have no idea of vram it is wd90c56-7x chip. i will see if that works.

riku wrote:

thanks for the answer, it is unsure if it fpm, i tried google. thats i asked here. it is yes 32M one. i do have a pentium board […]
Show full quote

thanks for the answer, it is unsure if it fpm, i tried google. thats i asked here. it is yes 32M one.
i do have a pentium board under test, but that one is not showing if it edo or not.
I removed other 32M, so pc has one simm of 32M. after little struggling i got cache + cpu WRITE-BACK Working!!! it needed to do odd things, jumpers and change cache rams. so 32M is maximum cacheable memory, so i removed other simm.
would be nice if someone has more optimal settings? 😀

Anyone please could point me to where i can get 1024 cache modules cheap? if i upgrade to 512k, then i can use 64M

About VLB card, i have wester digital (untested) have no idea of vram it is wd90c56-7x chip. i will see if that works.

The Asus PVI-486SP3 does not support EDO memory so if the memory works it's FPM

(Correct me if I'm worng as I'm not 100% sure. On other SIS 496/497 chipset motherboards it depends on chipset revision but I can not remember seeing anyone getting EDO memory working with the Asus PVI-486SP3)

I dont know much about the Western Digital VLB cards but my 1MB ISA card is very fast. I think I have read good things about them but testing all cards and seeing what card performs best and gives a good picture quality is the best option.

i will take edo simm and try it out, it is simple as that.

the WDC 90C31 is VLB card, google has only info about 16bit ones 🤣

edo ram just done bad to the post screen 🤣, can confirm not working :DDDD okey got my answer, it is FPM