successful overclock stories wanted

Overclocking a wallstreet would be pretty pointless, as you wouldn't be able to go very far with it. If you want 300mhz, buy a 300mhz processor on ebay, they're pretty cheap these days, although I doubt you'd be able to notice the difference of 8mhz. If you're looking for serious performance and you're married to the wallstreet, there are faster 3rd party g3 and g4 processors available, but the money you'll spend on upgrading a wallstreet would go a long way toward a pismo or even an original tibook.

i have been considering a pismo as well. right now the wallstreet is my backup/project laptop, and i thought an overclock would do it well if i could keep it cool enough to run. i'm getting an albook as my new main computer, and maybe a pismo will be coming as my backup soon.

Overclocking anything is pretty pointless as CPU upgrades for anything you're willing to risk destroying (read, inexpensive hardware) are cheap and plentiful.

That is, it's pointless if your only goal is more speed.

There's merit to performing the OC for the OC's sake, though. It's fun. Heck, for the fun of it, I grafted a beige G3's SGRAM slot to my Wallstreet II and installed 4 MB extra of VRAM just because. It didn't work, though. The extra 4 MB actually corrupted my color table. I didn't do a lot of diagnostic testing to see what the problem was. I'm pretty sure the RageProLT can address 8 MB of VRAM. I was expecting to see the benefit with an external display, but I never tested that.

I haven't OC'ed my Wallstreet(s), but I'm considering taking a 266 MHz card up to 300 MHz or a little more.

I'm interested in what your final speed will be. Post back if/when you do this!

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Drew

i'm beginning to look into the overclock more now. i'm trying to figure out how to keep the powerbook cool with a higher clock speed. i figure if i can get the bus down to 66 mhz with full compatability, i can clock the speed up for 400mhz to give the computer lombard settings. my only fear was lack of stability due to heat. i'm hoping i can use a lombard heat shield or even a pismo heat sink if i were to take out my modem (never used the thing in the two years i've owned this computer). right now with mozilla open (and after playing an avi, mov, and wmv at once) the temperature is only 54 degrees celsius according to gauge pro. that seems cool, but it was idling at 62 earlier, so i don't know why it's so different.

I really doubt you'll get your Mac to even boot at 400 MHz. Usually you can't squeeze more than 20% out of an overclocked CPU. That will get you to 300 MHz most likely, and in the tight constraints of a PowerBook G3, I wouldn't expect you to get much more than that. Heat will be your biggest problem. If you can get the heat pipe from a Pismo working, you might be in a better situation. You might even get to 333 MHz or so.

Heat will definitely be your biggest hurdle. Try shorting the fan so that it's always on, and maybe you can re-direct the flow to be more CPU localized. Or maybe you could just relocate the fan to the modem slot area. That will pull air more directly over the heat pipe when the fan is on.

I don't think you'll get the Mac working with a 66 MHz bus very well. I _think_ there are ROM difficulties involved. But, hey, give it a try. The worst that will happen is that the Wallstreet won't boot. I've tried running a WSII with a CPU upgrade from a WSI (the flash ROM was already set). I only got it to boot about 25% of the time, and only one time in 10 did I get the cache working. Supposedly these cards can't be reflashed once they are programmed...

Good luck,
Drew

comparing heatsinks, whatever i choose to put in will have to be modified. with the pismo heat pipe, i would put in another fan that would always run at low rpm to pull hot air out a vent that i would install in place of the modem door. 400 mhz would be nice, but 300 is a good (and safer) improvement in speed. last check on my temperature, i think i got it up to 68 for a little while, and it seems to be mostly when the hard drive is running at the same time that the processor is doing work. i've never had the fan kick in, so i don't know how hot the machine has to be for it to work.

pismo heatsink won't fit. the heat pipe is too long, and the heat spreader is too wide to fit where the wallstreet modem would be. i did find a heatsink from an hp laptop that looks like it would fit with much less modification.

A couple hours ago I overclocked my 266Mhz PowerBook G3 Series Rev 2 (PDQ) to 300Mhz without problems and yes, I do actually notice a speed difference in Panther. Booting and the applications I use on it are all faster.
Personally I think spending a little time soldering tiny resistors to OC the CPU to 300Mhz totally beats spending $10-$20 on a stock 300Mhz CPU and another $10-$20 on shipping&handling then waiting 2-4 weeks for it to arrive.

glad to hear about your success. something around 300mhz was the base benchmark i want to reach, and now i know that's easy. i'll start there (and try to see how the 66mhz bus goes) and then try to improve cooling and speed as time goes on.

I've overclocked a few Wallstreets - mot notably my parents which is as always going strong.

- Wallsteet 14.1" 233@300Mhz
- Mainstreet 12.1" cachless 233@266Mhz (you'd think this CPU would get higher due to a complete lack of cache, but alas). Later installed cached 233@266Mhz (300Mhz of parents was lucky I think).
- My Lombard 333Mhz@433Mhz (this was the easiest resistor configuration to move first, and to be surprise works a treat!

JB

Another thing to remember is voltage that the chip can draw after the overclock. I have 3 g3 towers and one went from 300 to 400 but the other would only boot after a 50 mhz increase, I think going from 266 to 300 is the safest and most reliable you will be able to go with on the wallstreet.