7500 MOBO Query

[chuckwagen]

Just dropped a 7500 motherboard with a 200 604e  in a 7200. I have a video card installed. Do I still need the 2 vram chips for startup? I have no video showing, but do have hard drive noise, etc. For memory interleaving, does the pair go in A1-B1, or A1-A2? Will it take 128MB chips? The 7200 did. Thanks..., chuckwagen

[neokm]

I know I did on a 7100 recently.  More importantly, you have to hear the start-up chimes.  I bought a "stripped" 7100 board for $2 on ebay and dropped it in my very first Mac - an old Performa 600 with the same box and power specs - then proceeded to load it up.  As I see it, you have got to have at least as much memory on board as is required on the OS system that you are starting up on - in the case of the 7100, I only had 8mb ram simms built in.  After I loaded it up with (odds and ends I had laying around) I ended up with a total of 104 mb ram and it booted right up.

I guess the same would be true with "vram" and what your HdD and OS has loaded on the start-up sequence for your video demands.  

FWIW - Hopefully others will answer your question better than I.

PS edit:  I had another 7100 board I tried first and I did not get the start-up chimes on it.  Tried everything - - including other HDD's and OS's that I knew to be in working order.  Everything was audible - ie. HdD's reving and lights a blinking - - - but no start-up chimes, and no boot.  I concluded that it this particular board had a faulty control chip.
 
 [ 03-01-2003, 04:21 PM: Message edited by: neokm ]

[kelly]

Hmm. You might need  some onboard VRAM.  

Seems to be the machine will boot up and then switch over to the Video Card.

But then again maybe not.  

http://docs.info.apple.com/article.html?artnum=18358

http://karchive.info.apple.com/

GURU should tell you about interleaving. If it's still around.

http://www.macupdate.com/info.php/id/3561

[krissel]

Interleaving is A-1, B-1; A-2, B-2...

[kelly]

Hey chuckwagen. Try asking here.  

Accelerate Your Mac BBS Upgrading Pre-G3 Macs

This is handy.

http://www.mathdittos2.com/columns/bh/bh010723.html

[chuckwagen]

GURU is great! Diagrams and everything. I am getting an additional vram chip, which costs half as much as the entire computer...

[chuckwagen]

I finally got it started. There was a bad 128 MB memory chip. It's still pretty flaky, a lot of freezes. I initialized the 2 GB hard drive and it won't take the OS 8.5 install disk. It stalls halfway through because an installation tome could not be found. The install disc is clean. So I tried the OS 8 disc and it bombs on an address error on the Mac OS screen. I have a 8.6 imac software restore disc I will try next. I have no scsi devices installed.

[Reiddm]

chuckwagen, I converted my 7200 to a 7500 sometime ago, and I had a problem with freezes and finder quit please restart, I ended up pulling the L2 cache, but I'm running a 233 daughter board from a umax, I don't know if that makes a difference or not, it runs so good (good, it has yet to crash) now that I'm not worried!
I'm not running any SCSI HD's, I installed a IDE PCI card and I'm running a new 80 gig, and a old 80 gig that I removed from my G3 after installing a faster drive. I'm currently running 9.1, looking forward to a G4 card to run 10.2! I love these toys!!!

[chuckwagen]

The software install disk from the iMac didn't work ("this isn't an iMac") but the iMac Software restore disk did, the second time. David, I'll try removing the L2 cache. I don't think the kids will notice the slowdown with Putt-Putt or DivaStarz (whatever they are)....