IIsi (onboard) ram upgrade.

[uniserver]

ok good news i removed the onboard ram from the IIsi.

and it still boots… just no onboard video. surprise, surprise

not to worry IIsi radius video card still works

Next, i have a dead powermac 6100 mb, looks like it has 8 meg ram… across 2 banks… removed one of the banks.

same amount of chips 8 … same pins too.

i will try to hot air flow those on to the IIsi and see if i now have 4 meg of faster onboard ram.

 

[uniserver]

ok did it…

I now have officially the only IIsi in the wold with 4 megs of onboard ram

* bows *

Not only does the new ram boot up, i noticed onboard video started doing 640x480 by default @ 256.

so that was kind of a nice screen resolution bonus.

pretty cool.. my testing continues.

some pictures.

[attachment=3]Screen Shot 2013-12-26 at 7.55.29 AM.png[/attachment]

[attachment=2]Screen Shot 2013-12-26 at 7.56.05 AM.png[/attachment]

[attachment=1]Screen Shot 2013-12-26 at 7.56.32 AM.png[/attachment]

[attachment=0]Screen Shot 2013-12-26 at 7.57.02 AM.png[/attachment]

 

[Trash80toHP_Mini]

Cool, have at it! :approve:

 

[uniserver]

What were your thoughts on this man?

well i can verify the 4 meg's from the dead powermac 6100 board worked!

the video does seem faster too. the after dark fishy screen saver that is on there… seems to flow more smoothly.

how far do you think we can push this?

so there is 8 spots for ram chips…

one thing that confuses me…

this doc:

http://tim.id.au/laptops/apple/legacy/macintosh_iisi.pdf

it says the IIsi comes with 2mb ram.

but any IIsi i have ever seen only has one meg onboard.

Oh unless it came with one onboard and 4 256k's ….

also Everymac: http://www.everymac.com/systems/apple/mac_ii/specs/mac_iisi.html

Details: *Onboard video is capable of supporting a maximum resolution of 640x480. If the optional NuBus adapter card is installed, a second video card can be installed to support a second display. The NuBus adapter also provides a 68882 FPU.

So looks like I got the 640x480 just by upgrading the ram to 4mb. interesting.

i was able to get 640x870 but it was pink only…. well now its blue only… (I'm booting 7.5.5 back up)

[attachment=0]IMG_1004.JPG[/attachment]

 

[MinerAl]

Awesome!

I asked a while ago if such a thing could be done to a 475/605. Think you could upgrade any Mac this way, or is the SI a special case?

 

[uniserver]

i guess its hard to say until someone does it

 

[MinerAl]

Is this your OC'd 29 si?

I have a 605 that needs recapping anyway...

 

[uniserver]

no that is my nice one.

This one has been playing a game of hot potato, I sent this one to mcdermd… but the sound was never right on it.

after he re-capped it, he got mad so i sent him another one. :-D

I'v tried to pawn this screwy sound one to couple people but when i tell them the sound is screwy that scares them off.

So i thought this would be prime candidate for some Ram testing.

Now its 4mb onboard ram !

a q605 recap @ normal $ would be fine for now… I'm broke.

 

[mcdermd]

That IIsi board did indeed drive me mad. I never could figure out a reason for the issue beyond attributing it to half-rotten traces or something.

 

[MinerAl]

So will you be upgrading your good board now?

 

[uniserver]

yeah i changed LEFT / RIGHT and ASC and it still does it Ah well its ok… if i leave it at "2" seems to be ok.. just slightly on the quiet side but no crackles.

 

[uniserver]

probably not right away… I am going to keep testing with this one and get different ram chip variations outta my system first… I think next, I would like to bump it to 8mb.

 

[onlyonemac]

So looks like I got the 640x480 just by upgrading the ram to 4mb. interesting.i was able to get 640x870 but it was pink only…. well now its blue only… (I'm booting 7.5.5 back up)

That's because of the monitor you're using. LCD monitors with those things often come out in funny colours.

 

[uniserver]

Nope You're wrong. Sorry.

 

[uniserver]

should i try for 16 megs?

I have a 32meg simm here with 8 chips on each side …

should i go for the gusto?

 

[techknight]

Why not, As long as it has enough available addressing in that circuit, i dont see why it wouldnt work.

 

[MinerAl]

If you're going to try 16, you might as well try it first. Might save yourself the 8MB step!

 

[Trash80toHP_Mini]

Try 640x870 again, but as GRAYS, not colors. [] ]'>

Awesome achievement, uni. :approve:

 

[uniserver]

Try 640x870 again, but as GRAYS, not colors. [] ]'>Awesome achievement, uni. :approve:

tried it … for some reason its stuck on blue….

but you must admit even in blue … 640x870 coming outta the IIsi stock video port is kinda cool!!!

at-least i think so.

-------------------------------------------------------------------------------------------------------------------

ok update on this ram upgrade!!!

the 1meg onboard ram in the IIsi consists of EIGHT, 128k 20pin ram chips.

the 4 meg onboard ram that i have just installed consists of EIGHT, 512k 20pin ram chips.

right now i am STUCK at 4 mess of ram, because i do not have any larger denomination 20pin ram chips.

Does anyone one a Powermac 6100 with 16 mess of ram?

if so will you please count the pins on the ram chips for me?

My hunch is any denomination above 512k per chip goes to a 24pin chip, witch would make it incompatible with the ram pads on the IIsi mainboard.

HOWEVER, it would be great!!! if the powermac had 1meg 20pin ram chips to make 16 meg's, then at least there is hope of getting 8meg's maximum(onboard) in the IIsi.