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Just a heads-up

LCGuy

LC Doctor/Hot Rodder
Was looking at OWC the other night and I found that they have brand new 16MB 30 pin SIMMs for $9.97.

I have no idea what happens in other countries, but here in Australia at least, 30 pin SIMMs bigger than 4MB are extremely rare, and when they do come up, are usually pretty expensive, and are also usually not new. Needless to say I've since ordered some...looking forward to finally maxing out my Quadra 700. Just thought I'd put the word out there, as this is an incredibly cheap way to max out an SE/30, Mac II series or early Quadra, not to mention that the brand new RAM also has a warranty.

 

Hotdog Zanzibar

Well-known member
Hmm... according to OWC, my Q840AV can use 72-pin EDO RAM. Has anyone tried using EDO RAM in a Quadra?

Also, I see they have 64mb 72pin SIMMs. I wonder if I can put four in the 840AV and get 256mb?

 

mcdermd

Well-known member
And here I thought the SE/30 took a long time to count up 32MB before it booted...

It would be awesome just because it is 128MB but does anyone actually come close to using it?

 

LCGuy

LC Doctor/Hot Rodder
If you're actually using the system for Photoshop, image editing, etc, then yes, you would come close to using it all.

Apart from that though....really its just awesome to have a 68k Mac with that much RAM in it. :)

(for what its worth I have an LC475 with 68MB and a LC630 with 132MB and they both take eons to do the startup RAM check)

 

LCGuy

LC Doctor/Hot Rodder
If you're running Mac OS 8, yes - hold down the Command and Option keys while opening the Memory control panel and turn off "Startup Memory Tests".

 

theos911

Well-known member
Hmm...

I think it is possible under system 7 as well. I remember doing it on my duos, long before I got my new 2300c with 8.5 . Gimme a sec, I'll try it on my 270c.

EDIT- Sigh* My memory must be failing me. I tried it under 7.5.5 on my 270c and 2300c; no option for it on either. Maybe 7.6?

I tried using the 8.5 memory CP under 7.5, but it crashes with an unimplemented trap. It might work with closer system versions, like 7.6 and plain 8.0 . However, I have access to neither of those.

 

coius

Well-known member
I think most stuff in 8.5+ is PowerPC code and not Fat binary. So trying to run that would bomb a 68k machine depending on how it tries to run it.

 

theos911

Well-known member
All of the extension swapping testing was done solely on my 2300c.

**I acquired a 7.6 install and will FTP it over once I get the 270c's drive re-partitioned. Btw- Why does 7.5.5 use 6.5 mb of RAM on my 2300c and 18mb of RAM on my 270c with the same set of extensions?

 

coius

Well-known member
is the 270 32-bit clean? how much ram do you have left?

also try trimming extensions.

 

LCGuy

LC Doctor/Hot Rodder
Also, do you have VM enabled on the 2300c? Back in the day it was advisable to turn VM on on PowerPC Macs, as it actually made apps use less memory.

 

theos911

Well-known member
Is the 270 32-bit clean?
Do you mean 24 bit vs 32 bit addressing in the memory panel? If so, what is the difference?

Test: It runs at 18,738 in 24 bit and 2,387 in 32 bit. I guess that solves that. Also, MpegDec now works :D

How much ram do you have left?
The 270c has 24mb of built in memory, which I believe is its max.

Also, do you have VM enabled on the 2300c? Back in the day it was advisable to turn VM on on PowerPC Macs, as it actually made apps use less memory.
The 2300c has 20mb of built in memory.

Test: It runs at:

No VM, No Modern Memory Manager: 6,330

 

No VM, Modern Memory Manager On: 6,373

 

22mb VM, No Modern Memory Manager: 5,995

 

22mb VM, Modern Memory Manager On: 6,065

It appears the MMM doesn't do much for the system software. Granted, I didn't try it with any apps. VM shaved 300kb of the SS, not a lot compared to 6mb, but a decent amount nonetheless.

Just for the heck of it, I tried it on my 270c:

A. First time booting it gave me death chimes and scared the living **** out of me.

B. It booted fine the second time.

With 32 bit addressing:

No VM: 2,404 (which is different from the 2,387 from last time for some reason)

26mb of VM: 2,518 *Would of used 22mb to be consistent, but 25mb was minimum)

So, the same does not hold true for 68k.

 

theos911

Well-known member
Thread thoroughly de-railed:

I was trying to find the highest quality that MpegDec can play with minimal stutter and keeping the menu responsive during play on my 270c.(33mhz '03 w/FPU)

This is what I found:

48 kbps 22mhz perfect playback, occasional stutter, interface locked

40 kbps 22mhz perfect playback, almost no stutter, interface responsive with 1 sec(ish) delay **

40 kbps 16mhz perfect playback, no stutter, interface real time responsive

I couldn't tell an audible difference between these and the original 64kbps, 44hz file anyway. However, at lower than 32kbps or 16mhz it gets garbled quick.

**If you need the higher quality you could probably boot with extensions off to free enough cpu to not stutter

 

trag

Well-known member
Hmm... according to OWC, my Q840AV can use 72-pin EDO RAM. Has anyone tried using EDO RAM in a Quadra?
Also, I see they have 64mb 72pin SIMMs. I wonder if I can put four in the 840AV and get 256mb?
EDO RAM can be substituted in any Apple machine which uses FPM RAM (30 pin SIMMs, 72 pin SIMMs, 168 pin 5V DIMMs) except for the PowerMac 7200 and Power Computing clones based off of the 7200.

The Q840AV will not address SIMMs larger than 32 MB. It treats them as 1/4 the capacity. So a 64 MB SIMM will be seen as 16 MB and a 128 MB SIMM will be seen as 32 MB.

Technically, the Q840AV appears to not use the full twelve address lines supported on 72 pin SIMMs. It only uses 11. The address lines are used twice (multiplexed) so that gives 22 address bits which yields 2^22 addresses or 4M addresses. The SIMM is 4 bytes wide (32 bits) so that's 4M X 4 bytes = 16MB. Then the 32 MB SIMMs have two banks, so one gets 2 X 16MB = 32 MB. The banks are addressed separately using the four RAS lines on the SIMM.

The PowerMac 7100 and 8100 behave the same way. Strangely, the PowerMac 6100, which has the same chipset as the 7100/8100, does not. It *will* address 64MB and 128MB SIMMs. However, I found that there's an extra PLD chip between the 7100's and 8100's memory controller and the SIMM sockets which intercepts/interprets the RAS lines and the higher address lines.

I think the 7100/8100 trade addressing larger SIMMs for addressing more SIMM sockets.

 

Hotdog Zanzibar

Well-known member
Thanks trag, that's good news. I bought a bunch of RAM off a guy on craigslist for super cheap several months ago, but didn't realize it was EDO until I got it home. Now I can throw some of the 32mb modules in and see what happens :)

 

trag

Well-known member
Thanks trag, that's good news. I bought a bunch of RAM off a guy on craigslist for super cheap several months ago, but didn't realize it was EDO until I got it home. Now I can throw some of the 32mb modules in and see what happens :)
You're welcome. There's an Apple Tech Note about EDO memory somewhere. I can't remember which one though. It says what I just repeated.

 

Anonymous Freak

Well-known member
And here I thought the SE/30 took a long time to count up 32MB before it booted...
It would be awesome just because it is 128MB but does anyone actually come close to using it?
When I used my SE/30 as a NetBSD server, I sure as heck used 128 MB of RAM.

Before doing that, I had the 128 MB in my IIci, which I used with a VideoSpigot to import and edit video. (The IIci really needs to be re-capped now, and is *VERY* flaky booting. I probably need to re-cap the SE/30 as well...)

 
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