Can I run my PowerBook G4 with no RAM chip in the lower slot?

Hi, Donna. Yes, it's fine to run your PB with the lower RAM slot empty.

Yes you can!

More then likely it came with RAM in only one slot when new... the thing is, running on half the RAM (if you have intensive programs that use a lot of RAM) it will run slower without it. Although 1 Gig is perhaps double what it came with new.

You could also try to switch the 2 RAM modules around slot for slot, and see if it's the slot or the RAM that is doing it... however, be careful doing this, as if it is the RAM, it could fault out the other (for now) good slot; and if it is the slot, it could fault out the other (for now) good RAM.

Not knowing how the lower ram/slot failed, it is usually (smartest) to remove the RAM from the bad slot, put the largest RAM module you can in the upper slot (1 Gig), and operate as such. This way the problem stays isolated and cannot fault out anything else on the circuit/board due to it's own problem.

Good Luck, which ever way you go...

Oh my! I have this problem. I wish there was a way to know if it's the RAM went bad or the slots. The idea that I could be destroying more RAM slots isn't pleasant to consider.

Problem seems compounded because I've been told RAM might test OK, might be okay for awhile and then go bad. So "bad RAM," could be in there but it would seem okay...till it goes bad and damages/faults the slots.

Any way to bring the slots back to life?

One of my 'hooks,' that's suppose to hold onto the RAM chips is missing....I guess that might be part of the problem.

The RAM actually appears to 'pop-out,' --- is that so?

Oh my.

You can, of course, but here's a recommendation based on experience. I have a G4 PB, the FireWire 800 model (1.25 Ghz), and it also suffered from the lower-slot syndrome. Imagine my surprise when I realized that I had been working with 256 MB of RAM instead of the 512 that was supposed to be standard...for several years! So I ordered a 1 GB module for the upper slot, and was pleased with the improvement in performance – until the logic board went blooey!

Needless to say, I was concerned about getting the computer fixed. It didn't help when some young dude from the Fashion Valley (CA) Apple Store told me over the phone that it would cost almost a thousand dollars to have it fixed (that's an in-house rate, I now know). The next afternoon I was down at the Fashion Valley shopping center, and on impulse I decided to pop in to the Apple Store in person. Well, lo and behold, I found out that if I was willing to be patient (like about three weeks' worth of patience), I could have my little G4 shipped to the Apple Repair Depot somewhere in Texas and repaired for a flat rate of $300 (I think this was 2005 or so).

Well, they replaced the logic board as well as my 1 GB module, which was damaged when the board decided to commit hara-kiri. But here's the kicker: the lower memory slot was repaired as well, and for the first time since I bought that machine, both slots were functioning. So I immediately ordered a second 1 GB module, and have been happy ever since with my 2 GB of RAM!

The funny thing is that I was one of the several thousand G4 owners who had appended their signatures to a petition complaining about the lower memory slot design flaw. My computer was too old to be included in Apple's offer to fix the problem (people with the newer 1.5 Ghz and 1.67 Ghz models were luckier). Also, I only had the one-year warranty, and had I purchased the three-year plan, it would have expired anyway.

As it was, I paid about the same amount of money to the depot as I would have spent on the extended warranty. It's funny how things work out sometimes.

All I can say is, if you have a few hundred bucks that aren't working too hard, inquire at the nearest Apple store about the repair depot option. I went from not knowing there was a problem with the lower slot, to being incensed about being unable to access half the memory capability of my G4, to having that missing half restored. In short, my computer's RAM was increased from 256 MB to 2 GB in a very short time.

I would highly recommend looking into this course of action, as having the max amount of memory makes the PowerBook operate more smoothly, more quickly, and more effortlessly. What a difference!

Hope this helps!

Oh my. Are there other systems of logic board going blooey?

Is having a faulty RAM slot a symptom of a logic board about to commit hara-kiri?

I just learned that, in my case, the RAM is in pairs and I just found out these pairs are 'programmed,' to work together and somehow my official pairs had gotten mixed up and become orphans with step-sibblings.

So now I've just reorganized the pairs to be properly matched again; there was a mix-up.

Now I don't know. I tried leaving the first DIMM slots empty but problems returned, 'cause I had it in my mind these slots are faulty. But computer freezing and not starting up with empty slots.

So I've just put the Mac Ram back in the first two slots. Computer System Profile reads all 4.5 GBs....but I'm expecting trouble. Memtest says everything okay but it said that before. I'll run it again for more loops.

Is having a faulty RAM slot a symptom of a logic board about to commit hara-kiri?

No, it's proof of a logic board that already has, in part. The RAM slots are soldered onto the logic board, and the way Apple "repairs" bad slots is to replace the board. Only the lower slot commonly fails, and many people have just decided to save their money and make do with 1gB of RAM in the good upper slot. Doing that has no adverse effect on the other operations of the logic board and will not shorten its life.

OK. I'm going to accept the idea that the first two slots can remain empty. That did work okay for me a couple of times (but my freezing problem returned, perhaps for other reasons).

So I'd now agree with others that the answer to specific thread question is: Yes.

Now, for two days, since "properly pairing," my RAM the computer has acknowledged all memory - But -- it froze up again from sleep mode.

It would not restart. Power light flashing three times. Pause. Flashing three times again, on and on.

I reset the Mac Ram in the first two paired slots. No change. I reset the Mac Ram and OWC Ram in the first four paired slots.

The computer started.

What "logic," I have left leads me to think it is the previously identified OWC Ram in slots 3& 4 that may be bad, go bad now and then. This came to my attention because in System Profiler they were only being seen as half their actual memory. Although now seen as their full memory.

Bummer than Ram looks okay sometimes then goes bad, then looks okay again.

This question might narrow down some possibilities: Can the Ram slots be faulty, then be okay, then be faulty again? (like Ram does).

Well...I'm gonna research a blinking 3x's power light and arrange the best deal I can to send it off for repair --- presumable a new logic board.

Of course, in my case, there is also the question of not wanting to throw good money after bad, so maybe get a new Intel Mac rather than repair a four year old PowerPC.

But I got more than a dozen things plug into this computer and some wouldn't make the transition --- humm, I'll have to start a list of Pro's and Con's.