Who here has overclocked macs?

[5300cs]

My boss gave me his B&W G3. Apparently a flip of a dip switch made it 400Mhz. I'm not sure what it was before ...

 

[joecool85]

My boss gave me his B&W G3. Apparently a flip of a dip switch made it 400Mhz. I'm not sure what it was before ...

Would have been a 350 most likely, those normally clock to 400 without problems.

 

[Spock]

I got my G3 overclocked to 450 but I got panics everytime I used the thing. Had to put it to 400 runs Tiger really nice.

 

[joecool85]

What did your G3 start as? G3 is a pretty broad term considering it encompasses everything from 233mhz to 900mhz.

 

[Lord Blackadder]

I've never overclocked a Mac myself, but muy current G4 has an OWC Mercury 1.4GHz G4 overclocked from 1.3. At the moment I don't own a Mac that is worth OC'ing - I have a G3 iMac and a bunch of 68k Macs.

The best Mac for "overclocking" is certain versions of the eMac, which use heavily underclocked CPUs; IIRC the 800MHz model uses a 1GHz or 1.25GHz rated G4.

I've never heard any reliable reports that any G5 sold by Apple is an overclock. Can anyone confirm this? As far as I know the 2.7GHz G5s are running at their rated speed.

Maybe some brave, wealthy soul can try bumping a dual 2.7 up to 3GHz?

 

[joecool85]

68k macs are great for OC'ing. I did my quadra 650, 33mhz up to 42mhz.

 

[840quadra]

- What is better: frying your new shiny Mac for a dew more MHz (no real world difference in speed) or using what you have for looong time period?

- Of course frying you new system!!!




Thats the answer of all overclockers

Actually going from a G3 350 to an overclocked G4 500 is a massive improvement(IMHO). I had no idea that programs were SO dependent on the Velocity engine for speed.

 

[Mord]

the dual 2.7GHz PM's are not overclocked they are rated at that speed by IBM, they could be aircooled but then it would sound like a dual xeon server aka a jet engine.

if you check ibm.com it's clearly stated they are sold to work at 2.7GHz, i dont know why people pull this overclocking bull out of their asses.

oh and my record overclock was a 300MHz G3 that i put to 550MHz with volt mods and a peltier. with a giant copper heatsink on it.

 

[joecool85]

the dual 2.7GHz PM's are not overclocked they are rated at that speed by IBM, they could be aircooled but then it would sound like a dual xeon server aka a jet engine.

if you check ibm.com it's clearly stated they are sold to work at 2.7GHz, i dont know why people pull this overclocking bull out of their asses.

I got it from hearsay right here on MR.

 

[Mord]

well he is wrong.

 

[Lord Blackadder]

The G4 seems to be the most overclock-friendly Mac CPU; 3rd party upgrade manufacturers like Powerlogix sell 100-200MHz overclocks regularly, sometimes even more.

The only Mac I have at the moment that I might consider screwing with is a Powermac 6100/66. Never looked into OC possibilities with that one...

 

[joecool85]

Output Enablers could get you up to 82mhz.

http://www.io.com/~oe/

That's where I got my OC chip for my 68k quadra. I didn't overclock my Power Mac with their jumper blocker however, I did it myself with jumpers from Radio Shack. Good thing too, I was able to get it to 315mhz whereas their jumper block will only take you to 300mhz.

 

[Lord Blackadder]

Wow, I didn't think those guys were still around. I guess there's enough Mac geeks playing with old computers to keep them going...

I remember when I got my first used Mac, a IIci that I still have. To this day I wish I could find the elusive DayStar Turbo 601 100MHz PPC upgrade for it at an affordable price...

 

[mymemory]

I had a beige G3 200 powermac and after overclocking it was just the same.

I think overclocking just give you a sense of speed that is not there at the end. in other words, no need of doing it.

 

[7254278]

I am considering OCing my sawtooth to 450 or 500, would this involve soldering?

 

[joecool85]

Nope, check this out:

http://www.xlr8yourmac.com/G4ZONE/G4YIKESOC/

 

[7254278]

I have a sawtooth not a YIKES!, will this work anyways?

 

[joecool85]

Nope...sorry, I just thought G4 and jumped on it.

Here is for your sawtooth...
http://power-mac-g4.com/g4clockup.html

sorry, looks like a PITA to me.

 

[7254278]

Nope...sorry, I just thought G4 and jumped on it.

Here is for your sawtooth...
http://power-mac-g4.com/g4clockup.html

sorry, looks like a PITA to me.

Link doesnt work LOL and wats PITA?

 

[Lord Blackadder]

I am considering OCing my sawtooth to 450 or 500, would this involve soldering?

maybe here. Look around xlr8yourmac.com for more articles. There is an article there somewhere about boosting a Sawtooth's bus speed from 100Mhz to 133Mhz, which will probably make as much a difference as boosting the CPU by 50MHz.

But be prepared to possibly fry your computer.

EDIT: It is probably a matter of relocating resistors on a jumper block to the correct settings for a new speed.

However depending on what speed you're shooting for you might need to bump the CPU's core voltage, which is more involved and riskier than just bumping the clock. Messing with the bus speed is also high risk.

Make sure if you are going to do it that you invest in a decent soldering iron - the El Cheapo ones at Radio shack really aren't up to the job, and may fry the little resistors or more likely burn your motherboard.

 

[LimeiBook86]

I was thinking of over-clocking my Quadra 840av from 40mhz to 48mhz but for $35 it's not worth it at all. I have dozens of other old Macs that I may want to overcloc kbut, meh...Or maybe I'll find a video card for the LC II/III and make it display more than 256 colors...I'd like that a lot

Actually my Quarda is running Mac OS 7.6 @ 1024x768 with 58mb of RAM and it runs great! It makes a good little print server...well that is if I can find the StylusRIP installer disk..."Can not find the folder SytlusRIP"...

But, I would be pretty interested in overclocking the old LC II/III models, I know MacAddict gave one an upgrade and everything, I'd mainly be interested in upgrading the video RAM for more than 256 colors...because 256 colors aren't too friendly when your browsing the web I have like 5 or 6 of these machines so if they break it's no big loss.

EDIT: Awesome!! Look what I found...Overclocking Mac LC III to 33mhz Looks simple enough... I'm trying this next time I go to PA (Where my old Macs live) !!

More cool links:
Clock Chipping from the Original Macs to the G4s!
Clock Chipping (Direct link to the LC III section)

 

[rickvanr]

I overclocked my B&W G3 from 400MHz to 450MHz shortly after the warranty was up. Rock solid for well over 4 years.

Patmian212, PITA (Pain in the a**)

 

[LimeiBook86]

I can't believe I forgot this!

I have a Mac Color "Mystic" Classic, replaced the original motherboard with a Performa 575 motherboard, bought the VRAM, and I just got an ethernet card for it online. Maybe I'll buy some RAM for it too.... The machines is one of my favorites and it's so cool too!

 

[840quadra]

well he is wrong.

No need to be so harsh.

Unless anyone here is an insider for the semiconductor devision of IBM we cannot be sure. It isn't that uncommon of a practice for chip makers to "clock" chips faster (among other minor changes) to get faster speeds from them.

It is the act of things like adding more cache or a minor instruction change that will let them "get away" with calling them new chips.

But then again I am on the outside of this. A guy that may know would be Aidenshaw, but he never checks these threads .

 

[840quadra]

I have a Mac Color "Mystic" Classic, replaced the original motherboard with a Performa 575 motherboard, bought the VRAM, and I just got an ethernet card for it online. Maybe I'll buy some RAM for it too.... The machines is one of my favorites and it's so cool too!

if you have that board (which I have in an actual 575) I would recommend ditching the 68LC040 for a true 68040 processor. The FPU will make some applications scream in comparison. It will feel like an over-clocked 575