Uncreative Labs

Joined: 27 Jan 2007 Posts: 274 Location: USA

well, diggin threw the graveyard(closet) i found my old mach 64 isa
this ones got 2mb onboard with a 2mb upgrade module, for 4mb

unfortunetly is messed up, as the text mode is all garbled symbols and graphics mode is barely usable. recently i found a pci version of the card, same chipset. on top of that, i found a packege of 20+ memory chips that are the exact same ones on the pci version. my isa version gots OKI chips m548262-60, while i can replace em with km 428c256j-6 as used on the pci one. i got 2 questions before i start
1. what else can be broken if not the memory chips
2. will the memchips on the pci version be compatible with the isa version? as they have the same gpu.

i dont fool around with old stuff much nowdays, diged threw my closet and found some stuff i forgot i had such as an old 8088 grid laptop with romdos that runs and a magnovox lappy ima try to get running next

also im wondering if i should install windows 95 on my 386 cause windows 3.1 is boring and it can hadle 95 ok

Joined: 02 Oct 2004 Posts: 594 Location: Western NC

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while i can replace em with km 428c256j-6 as used on the pci one

If they're both 256K 60ns, shouldn't be a problem...

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wondering if i should install windows 95 on my 386 cause windows 3.1 is boring and it can hadle 95 ok

Just make sure you give it as much RAM as it can handle. I tried it on a 386sx20 w/16MB and it was "tolerable". But the broadband connection I made with it was as slow as dial-up...

Joined: 27 Jan 2007 Posts: 274 Location: USA

before desolder the VRAM chips. is there a way to detertmine if its the memory or vpu i s bad?

Joined: 02 Oct 2004 Posts: 594 Location: Western NC

Without some sophisticated test apparatus, not really. If they're surface-mount chips, then be extremely careful about the amount of heat you apply (I'm somewhat of an expert in SMT)...

Joined: 27 Jan 2007 Posts: 274 Location: USA

well, im about 75% sure its bab ram, and the plan was to use a heat gun to take and reattach em. for the first time in over a year, i dug out the card and fired it up. still messed up but it its not the screen of random charachters anymore, it displays the ATI bios/model info n copyright and then it freezes in that mode while the computer continues to boot. then i was able to run a program that uses graphics mode by typing it out from memory and graphics mode had little rows of segments across the screen, wich means its most likly faulty memory. any suggestions for replacing surface mount chip?

Joined: 02 Oct 2004 Posts: 594 Location: Western NC

As far as the diagnosis, you could alternate between a freeze spray and the heat gun (being careful to concentrate the heat/cold on the specific "suspect" chip) while still in-circuit and running to see if there's any changes in performance.

SMT components require special soldering skills and equipment. Too much heat can damage the parts (and adjacent good ones) and pull traces from boards. If you've never done work like that before, I'd strongly suggest watching this first:

http://www.curiousinventor.com/guides/Surface_Mount_Soldering/101

though I'd discourage the "drag-soldering" technique he mentions...

Joined: 27 Jan 2007 Posts: 274 Location: USA

well, my use with a heat gun had some intresting results, the problem was corrosion under one of the ram chips, and decided to just replace them all. so i replace em and powered it up. the test mobo was an old k-6 HP, well the mach 64 turned on, but still a bit messed up with the new ram chips, so i pinch them down with my fingers till the garbled mess cleared up. the reheated the chips and then i was able to see the HP boot screen clearly, and was the first time ive seen this card display anyth ing reconizeable in the past year. although readable, something wasn't right, for some reason, the blue hp boots logo is usually blue n white, and it came out grey n pink on the ati card. it was gettin late so i had to go home, and when i tried it at home, one of the ram chips fell out, due to my crappy heatgun skills, fortunely it was the only one. so i'll go back to my friends house to borrow the heat gun next saturday and redo the ram chip. so, my questions are
1. are those samsung chips i replaced with 100% identical?
2. why are the colors not workin
3. why isn't text mode displaying anything except the blinkin dash mark
4.would corrosion be the cause of the video card failure?

also, im swapping out alot of expansion cards in my "beater 386"
the current setup for expansion cards was a promise eide max II
a dtk I/O card witha windbond chipset
a diamond speedstar 64 with 2mb
soundblaster 64 awe
3com 3c509b ethernet card
a 14.4k usr fax modem

im kind of wonding what i should upgrade

mabey ditch the eidemax n dtk card and drop in a scsi card
only card forsure staying is the sb64, cause its pretty much the last decent ISA soundcard made

so, wich would be best

scsi-
buslogic BT-545c
adaptec aha-1542c

ethernet-
3com 3c509c
an smc ultrachip pulled from a 1998 emachine
a novell card with dust all over it

video cards-
diamond speedstat 64 using a cirruslogin gd5434 chip with 2mb ram
ATI mach 64 with 4 mb thats gettin fixed hopefully
a diamond with an et4000 chipset but only 1mb ram
an STB wind/x card with s3 chips n 1mb
a trident 8900 or 9000

so wich will be good parts to use in a daily used machine? that will probly be running dos/wind 3.1 /95 and play old dos games and doing lite internet browsing and irc

Joined: 02 Oct 2004 Posts: 594 Location: Western NC

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1. are those samsung chips i replaced with 100% identical?
2. why are the colors not workin
3. why isn't text mode displaying anything except the blinkin dash mark
4.would corrosion be the cause of the video card failure?

Of those 4 questions, I could only speculate on the last one. Yes, corrosion could easily be the cause of the failure.

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scsi-
buslogic BT-545c
adaptec aha-1542c

My limited experience with SCSI would say go with the more "generic" one, the Adaptec...

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ethernet-
3com 3c509c
an smc ultrachip pulled from a 1998 emachine
a novell card with dust all over it

I've never had a 3com card fail on me, so that would get my nod...

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video cards-
diamond speedstat 64 using a cirruslogin gd5434 chip with 2mb ram
ATI mach 64 with 4 mb thats gettin fixed hopefully
a diamond with an et4000 chipset but only 1mb ram
an STB wind/x card with s3 chips n 1mb
a trident 8900 or 9000

More RAM is always better in video, and I'd only use a Trident or Cirrus card on a machine I really wasn't planning on keeping or using much. ATI Mach64 w/4MB is the winner (if fixed)...

Joined: 27 Jan 2007 Posts: 274 Location: USA

hmm, so what are the chances of cleaning of the corroded origninal ram chip and using it again? as these replacements are giving me doubts

and for a 386 with isa, wich would be better, ide or scsi?

Joined: 02 Oct 2004 Posts: 594 Location: Western NC

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so what are the chances of cleaning of the corroded origninal ram chip and using it again? as these replacements are giving me doubts

My concern would be that there may be other damage as well (possibly to the board itself or to the VPU chip). Any corrosion in electronics is not good, since the carbon residue (or even the water itself) would provide a conductive path to other circuits. FWIW, my 2nd choice on your list of video cards would be the S3 card...

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and for a 386 with isa, wich would be better, ide or scsi?

In the ISA days, SCSI was always a faster interface...

Joined: 27 Jan 2007 Posts: 274 Location: USA

wont beable to work on repairing ram chips on the mach 64, but ima use this week to get the rest the computer running good
current setup is now a 386@33mhz
16mb ram,
buslogic bt-545 scsi card
3com 3c509b
pcmcia card adapter for isa with databook chipset, should run with windows 95
SoundBlaster 64
USR model 460 8 bit modem, supositly 56k

2 things im not sure with, 1. when doing dir a: command on differnt disk, it will keep displaying the info from the first disk, not sure if my floppy drives are bad, or a boot sector virus called NYB that has seen to afect a handfull of my floppies as i constanlty use/bring home floppies from work... the disk seem fine under windows 3.1's winfile and would display the right files aftrer pressin F5.

2.ive never installed scsi before, so im kind of clueless other than selecting irq's and installing terminators, but im not familiar with the jumpers and gettin DOS installed cause fdisk aint finding a drive yet the bios claims its loaded. the 3 scsi drives i pulled were from old macs long since junked, i brought the drives home years ago by mistake as they were gettin junked for being small and i thought they were IDE drives and thought id use em somehow. so if anyones got info on the floppy issue or a "scsi 101" guide for installing dos on, id apriciate it.

on a side note, i got to try mike brutmans tcp stack and his irc client, very well made and very fast, that irc client was very fast and stable, only think i wish was there was the ability to switch between channels by pressin a key combo like ctrl+tab. i tried to run minuet,but running it off a floppy with no mouse was to much. the dl speed was great, but the floppy lagged to write it and load it.

Posted: Mon Nov 09, 2009 2:32 pm

386r, your floppy problem was known as phantom directories or such. if it does that DO NOT write to any other disks except the first one, you will fubar your disks if you do

Joined: 27 Jan 2007 Posts: 274 Location: USA

floppies fixed with a new cable. now im clue less as to settin up scsi hard drives working under dos, the scsi adapter detects the drive and the scsi id and terminator are setup. when using the built in scsi utility on the card, i try to test the hard drive, both verify and low level format fails, fdisk wont find the drive. what am i doing wrong , are drives ripped out of macs special?

Posted: Mon Nov 09, 2009 10:46 pm

usually no, i've got a couple of 230mb scsi drives pulled from a mac and put them in a pc and they work great. What scsi card are you using? Perhaps your termination isn't correct on the drive end of the channel, Check the drive's jumpers, even though it's got terminating resistors on it, it may be configured for them to be turned off. That has happened to me, i turned on the resistors and everything worked properly. Could also be termination on the card isn't set quite right. Are you using an Adapted 1540/1542B? i've got 2 of those, there is a fuse on it that may be blown in the corner, buy the external connector.

Joined: 27 Jan 2007 Posts: 274 Location: USA

ive tried an adaptec 1542 and a buslogic bt545. both ended up with the same results. ended up goin with the buslogic as its new and has a new styled extrenal connecter. i got some old quantum and a seagate st3600n. terminators on the card are enabled and i will double check the drive to see if its enabled