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Anthony the PC lover Mar 1, 2000 06:46 PM
My old mac flickers and freezes upon startup! Help!
When I start up my old (33Mhz, 8MB-RAM) Macintosh Performa 550, it goes to the little "Welcome to Macintosh" screen and the box just flickers/shakes and then the whole computer just freezes rendering the whole computer useless. Please help! I wanna revive my Mac!

[This message has been edited by Anthony the PC lover (edited 03-01-2000).]
Macee Mar 2, 2000 01:50 AM
Open up the case and locate the main CPU and install a NT adapter. It should just clip on. Next find and locate the toolbox boot ROM and reprogam it. Use a zip disk with ms dos on it. Find the speed connecter inside on main board and jumper down to decrease speed output. Next locate SCSI bus and install a speed adapter, probably 1/4 shoud do the trick. On your screen install a new window. Then boot with new software and you shouldn’t have any flickers or shakes. Should have solid pic with probably Gates smile. Enjoy
sblunden Mar 2, 2000 10:53 PM
try booting off the system CD and try to disk repair and/or reinstall the system
or try to boot with extensions off (hold down SHIFT on startup).
or boot of a Nortons disk and run the repairs

hope something helps
Anthony the PC lover Mar 9, 2000 04:19 PM
Thanks, but none of that works...any other suggestions? Please help!
iMan_ca Mar 14, 2000 03:06 PM
Your copmuter might have a hard ware problem, it could be toast. Look at the logic board (Motherboard) and see if the memory is in correct and there is no dust. Check the battery to see if it has leaked. Make sure the power cord is good and there is no power problems, make sure the computer is not to close to any thing like a TV. If you have other devices pluged into the same powerbar as the computer that can casue the screen to go strange. Boot from the CD,or with the shiftkey down, if you still crash you have a dead Mac.
finboy Mar 15, 2000 07:21 PM
You probably have a bad picture tube (a 550 is an all in one) or a bad power supply.

If you're a college student, the university may have a cheapo repair shop on campus that you can take it to.

Also, try pressing command(apple)-option-p-r and holding them while it boots. That might fix the screen resolution. If that works, make sure that you replace the system battery when you can. Just open the back and slide the motherboard out and you'll see the battery holder. Batteries are available at your local Radio Shack (and that's about ALL that anyone should EVER purchase there).
Steverino Mar 15, 2000 11:33 PM
Could be a hardware problem though a Sad Mac is more likely. One of the first things at bootup is the memory check.

Could be software. Corrupt System or boot blocks come to mind.

Somebody suggested a boot off a CD. Can you? If not a CD how about an emergency floppy?

The floppy is the better barometer because a SCSI problem (loose or ill-fitting termination or cable) would be bypassed.

If you can alt boot off a floppy then the hard drive or SCSI chain (what little of it there might be) has problems. If you have the same problem with a floppy then look at the hardware. The standard thing would be to pop it open and reseat all chips.
zac4mac Mar 19, 2000 02:34 AM
do you know what system version you have? 550's shipped with a special version of sys 7.1(7.1P3, seems like mine was 7.1P6) and will run on as high as sys 7.6.1 with the proper enabler(332 I think) It should boot from a Norton 3.5 CD or a Sys. 7.5 CD; hold the "C" key until you see a happy mac...another good thing to try is check the CMOS battery(3.6v lithium), just slide the motherboard out the back and check the voltage, if it's under 3.5 volts, replace it. Old machine but one of my all time favorite models...
MACOSXER Mar 20, 2000 12:49 PM
well this happned to me on my G3 i removed the hard drive then started up off the Apple CD an changed the start disk to cd the used drive set up to erase the drive the installed and was wizing a way
Zwilnik Mar 20, 2000 03:22 PM
The usual cause of events like these are dead PRAM batteries (especially on older machines).
Try clearing the PRAM on startup (hold command-option-P-R all at once, let it restart twice, then let go of the keys). If it starts up with a default screen, then you need to replace the battery. about £3. I've had to do that on pretty much all of my older machines (LCIII's, and even a Performa 5320)
Anthony the PC lover Mar 21, 2000 04:49 PM
I appreciate all your help guys, and Im constantly trying your easiest solutions, to no avail. Does it help to inform you that my problem came right after I tried to make a picture my background screen? Could that have caused this?
zac4mac Mar 30, 2000 03:52 PM
now that you mention it, yes it could be the cause...what type of image and how big was it? test that idea, try starting from a CD or zip and so into your boot drive and trash all the preferences relating to the display...also, slide out thre motherboard and remove the VRAM and clean its contacts with a pink pencil eraser(you should have one 256k VRAM module and one 72pin DRAM slot)
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