Sweeeet. Dual 1.2GHz G4 a reality.

outsider

<a href="http://homepage.mac.com/schrier/pmg4_1000_1200.html"; target="_blank">http://homepage.mac.com/schrier/pmg4_1000_1200.html</a>;



As long as you don't mind overclocking. And remember, YMMV. If 1.2GHz is a possible frequency, maybe the 7455 is MHz friendly.

crusader

Now, when is someone going to explain how to overclock my new iMac?

crusader

Mmmmm...

Dual 1330s...

eugene

I would be wary of doing this. The heatsink gets very hot to the touch on my machine at stock speeds.

matsu

hmmm... unfounded excitement brews...



But if the new G4's are over-clock friendly, does that mean we'll see higher speeds sooner, rather than later?



Eugene, time to get a big fan just like the PC over-clockers use. Buying a dual Ghz, and boosting it to a dual 1.33 after the warantee expires would provide quite a nice little boost.

eugene

I probably won't, I stink with solder.



And the thing is loud enough as it is.

outsider

He didn't use any extra fan for cooling. If anything, this would be a good time to remove the stock cpu fan and replace it with a quieter an bigger fan that moves more air. I would maybe go with a gamma type turbine fan. They are very quiet and move lots of air. (up to 10CFM)



<a href="http://www.nidec.com/gamma28.html"; target="_blank">http://www.nidec.com/gamma28.html</a>;



The Gamma 30 and Gamma 32 move way more air but are much bigger.

onlooker

I don't think I'll over clock mine either. If I would have known I may not have purchased the Apple Care Protection Plan,(&lt;-The only thing hat has shipped so far) but I did, and I'd rather be safe than sorry.

onlooker

I'm thinking maybe now that I've read it.

I would definately need a quieter yet more powerful fan, and maybe some other method of cooling.



I'll see how I feel about it after it get's here.

eugene

10 CFM is very low. I have 50 mm fans that blow &gt;20 CFM. The fan on the G4 heatsink is 60 mm, I think. I haven't opened my case in a while.



You can probably put a Delta "Black Label" in there and get ~40 CFM from that one fan alone. It'll sound like a turbine though.



[ 02-25-2002: Message edited by: Eugene ]</p>

matsu

If the thing over-clocks safely to 1.33Ghz that would put the claims of 30% clock rate increase when using SOI spot on the money. Now if only mot could throw a die shrink (.13u) and low-K dielectric at this thing too, we might see a 2+ Ghz G4 before the end of the year!

onlooker

Eugene, and Outsider's fan speculations seem a little conflicting. Not that either of them are incorrect, but between the two of them I have become confused.



So will the fan Outsider is talking about provide more cooling, and yet be quieter than the stock fan?

codewarrior

If the max multiplier on the current G4 is 10x then to get past 1.33 GHZ they are going to have to go to a faster front side bus.

eugene

Onlooker, the fan on the heatsink of the G4 probably moves at least 20 CFM, if not more. The turbine fan The Outsider suggests above only moves half that volume.



If you want to increase your cooling, you're probably going to have to sacrifice noise...unless you're willing to jury-rig some extra fans or make some case mods to put a bigger fan on the heatsink...



Lots of PC users use ducting with larger fans sucking in outside air and focusing that air on certain components. This an incredibly bad idea unless you have a good filter keeping dust and lint out. With the dual 1 GHz, you can probably add a 40 or 50 mm fan on the side of the heatsink.



If you don't have any PCI cards, you might be able to add an intake fan where the slot openings are...That might disrupt the circulation inside the case though, considering the 120 mm exhaust fan is right there already.



The biggest problem is not having a way to read CPU temps and gauge whether the modifications are effective or ineffective...or even detrimental...



[ 02-26-2002: Message edited by: Eugene ]</p>

little mouse

danget! how come no one ever does a webpage saying how to overclock an old imac

since i have one i want to know, maybe even get it up to 700mhz, i would love that. <img src="graemlins/smokin.gif" border="0" alt="[Chilling]" />

outsider

If the max multiplier on the current G4 is 10x then to get past 1.33 GHZ they are going to have to go to a faster front side bus.



The max multiplier on the 7455 is 16x.

jeremiah rich

Dang... I am starting to get excited about how fast these things will truly go....

anders

[quote]<strong>The max multiplier on the 7455 is 16x.</strong><hr></blockquote>



Anyone know what it is on the new iMac? (then perhaps we can have an idea of when it will go 133 Mhz)

outsider

Oops, I should be more clear . The max multiplier on the 7455 CPU from motorola is 16x. The multiplier support on the Apple motherboard may be lower. But on the new machines it's fairly easy to fix since the daughtercard holds the multiplier.

onlooker

Eugene, and Outsider. Where is a good place online to look for replacement fans. I could have posted this at HardOCP, or Ars, but I figure you guy's seem pretty knowledgable about this stuff.

outsider

<a href="http://www.plycon.com"; target="_blank">www.plycon.com</a> has a nice selection.