The 244 chips are bus buffers, probably related to RAM bus, each chip does 8 bits. The mod is some fix done in the factory to solve some problem. Later revision if one ever happened would have it incorporated into the PCB.
T-04YBSC, a new YMF71x based sound card & Official VOGONS thread about it
Newly made 4MB 60ns 30pin SIMMs ~
mida sa loed ? nagunii aru ei saa 😜
It is possible that the traces which go to those pins were having more noise or cross-talk than anticipated, so the capacitors are added for filtering. Usually you want to over design in CAD to avoid embarrassing post-production fixes like this. It would be better to include solder pads and not use them than to do what was done here. Alternately, it is possible that some previous user added these capacitors for reasons of filtering.
Plan your life wisely, you'll be dead before you know it.
thanx guys 😀
My 40mhz crystal came today so I decided to follow the advice I was given to do. everything in 1 shot.
Removed the keyboard din from my famous broken biostar motherboard which gets mentioned in nearly all my posts.
Removed the din on chicony board ready for to swap, cleaned the blue corrosion with vinegar and plastic pryer tool, checked under the chip near the connector but luckily no corrosion inside.
New shiny connector installed
Blue corrosion gone for now
After putting it all together I put in the 40mhz crystal and. changed the pin to run full clock now and was. rewarded with 160mhz, details on my amd133 thread, don't want to double post that.
Nice work. Interesting to see so many through hole resistors and caps on this board. I'm working on a 386 board now that has mostly SMD in those places.
Plan your life wisely, you'll be dead before you know it.
wrote:Nice work. Interesting to see so many through hole resistors and caps on this board. I'm working on a 386 board now that has mostly SMD in those places.
wrote:Nice work. Interesting to see so many through hole resistors and caps on this board. I'm working on a 386 board now that has mostly SMD in those places.
Thank you. From my understanding smd is a newer and cheaper to implement technology, so perhaps the chicony were stuck using old tech, which could explain the messy factory fix, just guessing here.
Im also interested about clocking the isa bus to 10mhz what you mentioned earlier to me. There is a 14mhz soldered crystal, I assume its halved and running isa bus at 7mhz so would I need to replace that crystal with a 20mhz to clock the isa to 10mhz?
