c60b-dk@buddy.Berkeley.EDU (John Sasinowski) (05/03/88)
I know that the Unix PC's motherboard contains 72 64K DRAM's (which give it 512K memory). I have several questions: 1. Can the 64K DRAMs be pulled out and replaced with 256K DRAMs (thereby putting 2Mb on the motherboard) ? 2. If the above upgrade is possible, what modifications to the system software is necissary for the computer to recognize the added memory? Will it interfere with the expansion ram? 3. Can you add chips to the 512K ram card to give it a full 2Mb? 4. Are there any difficulties with the above modifications (eg, desoldering parts of the motherboard, adding jumper wires, etc.? Thank you in advance. John Sasinowski c60b-dk@buddy.berkeley.edu.arpa
sadler@shorty.CS.WISC.EDU (Jonathan Sadler) (05/04/88)
In article <2951@pasteur.Berkeley.Edu> c60b-dk@buddy.Berkeley.EDU (John Sasinowski) says: > > I know that the Unix PC's motherboard contains 72 64K DRAM's >(which give it 512K memory). I have several questions: > > 1. Can the 64K DRAMs be pulled out and replaced with 256K > DRAMs (thereby putting 2Mb on the motherboard) ? Yes they can. There was a message posted to unix-pc.general on 19 Feb describing this procedure. This procedure has been tested. If you would like a copy of this message, I would be happy to mail it to you. > > 2. If the above upgrade is possible, what modifications to > the system software is necissary for the computer to > recognize the added memory? Will it interfere with the > expansion ram? Just a few jumpers.... > > 3. Can you add chips to the 512K ram card to give it a full > 2Mb? Yes, this upgrade was reposted at the same time as the above program. > > 4. Are there any difficulties with the above modifications > (eg, desoldering parts of the motherboard, adding jumper > wires, etc.? The above DOES NOT involve any "pin 15 on IC452 to pin 3 on IC403" style jumpers. It does involve bridging a few solder pads. The real problem involves the 72 chips. Thats 16 pins per chip... 1152 pins per motherboard/ram-card.... There is always the chance that you will "lift" a trace and botch the board. People have done this upgrade, but they were not novice soldering iron users. > >Thank you in advance. > >John Sasinowski >c60b-dk@buddy.berkeley.edu.arpa > If you have any questions about the memory setup on the UNIX-PC feel free to ask. Jonathan Sadler Computing Systems Labritory (CSL) University of Wisconsin - Madison INTERNET: sadler@cs.wisc.edu SNAIL MAIL: Jonathan Sadler sadler@csd4.milw.wisc.edu 2350 Comp Sci + Stat (CSL) UUCP : ...!uwvax!sadler University of Wisconsin sadler@uwvax.UUCP Madison, WI 53706 BELL NET: (608) 262-2389 "For amongst all people there is injustice."