km@emory.uucp (Ken Mandelberg) (01/07/88)
The documentation says no, but I'm wondering if there
is any trick for using a 1.5Meg Combo card with a
.5 meg Ram card and getting the full 2.0 meg out of
it.
Apparently if you have a .5 meg card, you are supposed to
only populate 1 meg of the Combo card. I guess that way
the .5 meg card replaces the vacant half meg on the combo
card, and all looks contiguous.
--
Ken Mandelberg | {decvax,sun!sunatl,gatech}!emory!km UUCP
Emory University | km@emory BITNET
Dept of Math and CS | km@emory.ARPA ARPA,CSNET
Atlanta, GA 30322 | Phone: (404) 727-7963law@mtunb.ATT.COM (Larry Weber) (01/07/88)
In article <2435@emory.uucp> km@emory.uucp (Ken Mandelberg) writes: >The documentation says no, but I'm wondering if there >is any trick for using a 1.5Meg Combo card with a >.5 meg Ram card and getting the full 2.0 meg out of >it. > >Apparently if you have a .5 meg card, you are supposed to >only populate 1 meg of the Combo card. I guess that way >the .5 meg card replaces the vacant half meg on the combo >card, and all looks contiguous. >-- >Ken Mandelberg | {decvax,sun!sunatl,gatech}!emory!km UUCP >Emory University | km@emory BITNET >Dept of Math and CS | km@emory.ARPA ARPA,CSNET >Atlanta, GA 30322 | Phone: (404) 727-7963 You CANNOT get a full 2MB expanion memory with a combo card. The reason is the the combo cards do not sense which slot into which they are inserted. They always assume they are in slot 1. In the 7300 there are 4 0.5MB expansion slots. If you put a normal 0.5MB RAM card in slot 1 it uses the number 1 slot. If you put it into slot 2 it uses the number 2 slot. If you put a 1MB RAM card in slot 2, it will use memory slots 2 and 3. If you put a 1MB RAM card into expansion slot 3, the memory will exist in memory slots 3 and 4. Finally if you put a 2.0MB RAM card into expansion slot 1, its memory will use memory slots 1, 2, 3, and 4. Now a 1.5MB Combo card thinks it is in expansion slot 1, hence its memory will go into memory slots 1, 2, and 3. The 0.5MB memory slot number 4 is not used, and cannot be accessed by a RAM card because there is no fourth expansion slot. One other item about memory placement. On the 7300 physical memory may have at most 1 hole. If you do not have a full 2MB on your motherboard, the space between the motherboard and the first expansion slot counts as one hole. Hence you would not be allowed to put a 0.5MB RAM card in expansion slot 1 and a second one in expansion slot 3 (you could put the second one into expansion slot 2, however). Larry Weber mtunb!law