Mac Mini 1.5GHz CPU question

[cobalt60]

I just purchased what was advertised as a 1.5GHz Mac Mini G4. I did not boot it up yet. I disassembled it and checked the writing on the CPU. It is labeled as a 1.25GHz 7447b. The main-board is also labeled as 1.25GHz.

Is it safe to assume this is *not* a 1.5GHz model? Apple wouldn't run a 1.25GHz CPU at 1.5GHz stock in a Mini G4, would they? The seller had multiple units for sale, so I can easily see that the seller had a mix of 1.5GHz and 1.25GHz and didn't know it.

 

[Nixontheknight]

I just purchased what was advertised as a 1.5GHz Mac Mini G4. I did not boot it up yet. I disassembled it and checked the writing on the CPU. It is labeled as a 1.25GHz 7447b. The main-board is also labeled as 1.25GHz.

Is it safe to assume this is *not* a 1.5GHz model? Apple wouldn't run a 1.25GHz CPU at 1.5GHz stock in a Mini G4, would they? The seller had multiple units for sale, so I can easily see that the seller had a mix of 1.5GHz and 1.25GHz and didn't know it.

It's probably not a 1.5GHz model, it's probably been overclocked to 1.5GHz, like I wanted to do on my MDD before I killed it

 

[cobalt60]

Would there be evidence on the board of an overclock? Somewhere I should look for evidence of hand-soldering?

 

[Nixontheknight]

Would there be evidence on the board of an overclock? Somewhere I should look for evidence of hand-soldering?

there probably wouldn't be much evidence, but try looking for some flux (usually less glossy than other parts of the board) around the board which might suggest someone moving the PLL clock configuration resistors

 

[cobalt60]

I just looked at the PLL location. Yep you're right. Has 0 jumpers, 3 look like they were popped off with a knife. Wonder how this is going to play out with trying to get a refund...

Thanks

 

[Byrd]

The other benefit of the "silent upgrade" 1.5Ghz Mac Mini G4 was 64MB soldered VRAM - you're not at all getting what you thought you were getting.

 

[Phipli]

Its more likely a 1.25GHz Mac Mini running at 1.25GHz. I'd be surprised if it was an overclock even. Someone just copy+pasted a listing or something, or mixed up which one they sent.

 

[cobalt60]

The overclock is confirmed. It has smooth unmolested solder pads where the blank would be for 1.25GHz, and looks like the other 3 PLL jumpers were just broken off with a knife (with 4 missing jumpers, that is the setting for 1.5GHz). I opened a return request.

There's one on eBay right now advertised as 1.5GHz. The screenshots show 1.5GHz (they did for the last one though too). However, the sticker underneath says 1.42GHz. Is it safe to assume this is a 1.42GHz model that has been overclocked to 1.5GHz? Or did Apple actually have 1.42GHz written on the 1.5GHz models?

Are there other ways to tell if it's a genuine 1.5GHz? serial number, model identifier, processor name (version)?

 

[aeberbach]

The overclock is confirmed. It has smooth unmolested solder pads where the blank would be for 1.25GHz, and looks like the other 3 PLL jumpers were just broken off with a knife (with 4 missing jumpers, that is the setting for 1.5GHz). I opened a return request.

There's one on eBay right now advertised as 1.5GHz. The screenshots show 1.5GHz (they did for the last one though too). However, the sticker underneath says 1.42GHz. Is it safe to assume this is a 1.42GHz model that has been overclocked to 1.5GHz? Or did Apple actually have 1.42GHz written on the 1.5GHz models?

Are there other ways to tell if it's a genuine 1.5GHz? serial number, model identifier, processor name (version)?

Yes Apple labelled the 1.5GHz as 1.42GHz (at least the one I had, which did have the 64MB VRAM) - officially the 1.5GHz didn't exist. You can look up the serial number.

 

[ArmorAlley]

I just purchased what was advertised as a 1.5GHz Mac Mini G4. I did not boot it up yet. I disassembled it and checked the writing on the CPU. It is labeled as a 1.25GHz 7447b. The main-board is also labeled as 1.25GHz.

Is it safe to assume this is *not* a 1.5GHz model? Apple wouldn't run a 1.25GHz CPU at 1.5GHz stock in a Mini G4, would they? The seller had multiple units for sale, so I can easily see that the seller had a mix of 1.5GHz and 1.25GHz and didn't know it.

I always ask the seller of mac minis for the serial number before I even bid.
I use this everymac.com to check the serial number: https://everymac.com/ultimate-mac-lookup/
You may have difficulty getting a refund from eBay, given what you have done to the mac mini.
If you just want a mac OS 9 machine, 1250MHz is more than fast enough.

 

[Phipli]

I always ask the seller of mac minis for the serial number before I even bid.
I use this everymac.com to check the serial number: https://everymac.com/ultimate-mac-lookup/
You may have difficulty getting a refund from eBay, given what you have done to the mac mini.
If you just want a mac OS 9 machine, 1250MHz is more than fast enough.

Problem is that 1.5GHz G4 Mac Minis never officially existed, so the serial on a real one would report 1.42GHz.

That said, it would have caught this 1.25GHz one.

 

[ArmorAlley]

Problem is that 1.5GHz G4 Mac Minis never officially existed, so the serial on a real one would report 1.42GHz.
That said, it would have caught this 1.25GHz one.

What you say may very well be true.
Everymac.com does give me info on 1500MHz Mac Mini G4s though via the link above.
And it has been accurate so far.

 

[Phipli]

What you say may very well be true.
Everymac.com does give me info on 1500MHz Mac Mini G4s though via the link above.
And it has been accurate so far.

View attachment 59016

Oh interesting. Perhaps they just do it off the date or something.

Useful.

 

[cobalt60]

You may have difficulty getting a refund from eBay, given what you have done to the mac mini.
If you just want a mac OS 9 machine, 1250MHz is more than fast enough

What I've done; you should have seen what the previous guy did. Missing RAM clip, broken motherboard mounts, missing screws. I've repaired electronics professionally for 15 years, this thing will go back together in better condition than when I've received it.

As far as just wanting an OS 9 machine, no, that is not what I want. What I want is a Mac Mini with 64MB VRAM and a G$ CPU with a minimum rating of 1.42GHz or 1.5GHz (whichever was included with the 1.5GHz Mini)

 

[herd]

I don't think the speed markings on 7447 chips mean much. I've seen "1250" parts work fine at 2GHz and "1700" parts not. If anything, I'd go by the mask rev if you don't want to test it.

 

[cobalt60]

I believe it probably runs fine at 1.5GHz, but I wanted the 64MB VRAM, and a chip I believe would be more likely to run at 1.58GHz. I understand the seller's confusion, but wish he would have accepted the return with less arguing. Looking at his history, he has sold other Mac Mini 1.5GHz, as well as a lot of other Macs from that era. I feel like he should know more about the products he is selling, but yes, I could have researched how to find the exact model by the serial number.

Assuming he isn't being deceptive, atleast now he knows what it is; a 1.25 overclocked to 1.5. He can relist it as such, and now he can include that information so the next buyer knows exactly what they're getting. A 1.25 OC'd to 1.5, and presumably found to be stable, is still probably worth more than a stock 1.25.