eMac 800Mhz -> 1.33GHz conversion

[vga4life]

Now, I'm proud to tell you all that I've broken the Gigahertz barrier with my 700 Mhz eMac, and most important, at STOCK VOLTAGE. One of the things I've had to change is the stock cooler, and now I'm running it with a Pentium 4 All-Copper Heatsink and a 80 mm fan running at only 5v, wich is all it needs to stay cool even running Folding@Home 24/7.

Extraordinary work! How did you attach the new heatsink?

-vga4life

 

[0939084]

Someone interested in selling me the required connectors?

Hey, I was wondering if anyone could sell me the required connectors for this. I have a genartion 1 emac, and I have the DCB although it would be preferable to use the connector above instead. I just don't have the soldering skills to build these connectors myself.

 

[rmanger]

1.58GHz @ 1.425V

Well, after using my 1.58GHz Gen3 eMac, I've deemed it less stable than it needs to be. Less stable in this case means 1 kernel panic about every 3 weeks. My rate of kernel panics was much lower before the overclock, about 1 panic every 6 months. The reason why I caught on to the instability was when my eMac embarassingly kernel panicked at a recent LAN party during the screensaver!

So I've turned the Vcore voltage down to 1.425V, hoping this will improve stability. It seems to work, for now...

Here's the updated list:

1.25GHz, 1.350V (Original Settings): Works stable

1.5GHz, 1.350V: Works stable

1.58GHz, 1.350V: Kernel panic on startup
1.58GHz, 1.425V: Works stable
1.58GHz, 1.450V: Works fairly stable

1.67GHz, 1.350V: No startup
1.67GHz, 1.450V: Kernel panic on startup
1.67GHz, 1.475V: Kernel panic on startup
1.67GHz, 1.500V: Works, but unstable
1.67GHz, 1.550V: Works, but unstable

 

[lbodnar]

Power button!

...
And it's not powering up.
...
jeff

Jeff, (and others)

You still have to use eMac's power button to switch it on!

I had quite a few emails about that. The PC PSU provides the power all the time even when the eMac is off or asleep. This is how analog board on eMac works as well, it just drops voltages a little bit (20v->12v, etc)

 

[stolfi1]

hey guys if any of you have the old emac casing left after your mod I need to buy one i would prefer it come with the power cable to please pm with your price.Sorry if this post is unwelcome

 

[rmanger]

D'oh! Back to 1.5GHz again...

After testing out 1.58GHz @ 1.425V Vcore, I've convinced myself of two things.

If you care about stability:
DO NOT MESS WITH THE VCORE VOLTAGE.
DO NOT OVERCLOCK PAST 1.5 GHZ!

This comes as a result of a kernel panic while using TextEdit. 🙁

Since I don't want my computer crashing in TextEdit or screensavers, I've decided to just clock back down to 1.5GHz and reset the Vcore back to its original 1.350V. This seemed to be the most stable back then anyways, since I have never experienced an inkling of instability with this config.

Maybe I just didn't get a lucky processor, or maybe it's a software conflict. Who knows. I guess I should be happy that I got a 20% speed boost for free... 😱

 

[Rod Rod]

I guess I should be happy that I got a 20% speed boost for free... 😱

May the time you spent on the mod be more than gained back by the time you save by making your machine faster. BTW that's pretty brave of you to take an eMac to a LAN party. Did you transport it in a custom wheeled case?

 

[rmanger]

No custom wheeled case. Just old fashioned lifting with the arms. 🙂
After a while, you get used to carrying it one handed while unlocking your car door...

My friends and I are not really heavy gamers. The fastest machine is an AMD FX-53 3200+ w/ Radeon 9800 All-In-Wonder Pro. Of course, my machine is the slowest 🙁 , but we still have fun playing WarCraft III (and lots of it), UT2004, Diablo II, and the like.

But I did feel better when my friend's younger brother brought a 1.7GHz P4 machine last Saturday. I didn't have the slowest machine that day for sure!

 

[skibummer]

Overclocked today

Just like to let you know that I just over clocked to 1.27 (1.266) from 1ghz. It seems stable enough, no crashes or kernal panics, with video compression, itunes and seti@home going on at the same time for hours. Thanks for the great instructions. Xbench rating up 20 points!

 

[netjosh_granada]

-vga4life

Quote:
Originally Posted by netjosh_granada
Now, I'm proud to tell you all that I've broken the Gigahertz barrier with my 700 Mhz eMac, and most important, at STOCK VOLTAGE. One of the things I've had to change is the stock cooler, and now I'm running it with a Pentium 4 All-Copper Heatsink and a 80 mm fan running at only 5v, wich is all it needs to stay cool even running Folding@Home 24/7.


Extraordinary work! How did you attach the new heatsink?

-vga4life

As I'm using the eMac logic board on a new case, this Heatsink mod was something necessary because I didn't want the standart Heatsink to take a lot of space in the new case apart from being more difficult to install a fan on it.

This is how I did it:

1. Buy a standart Pentium 4 Heatsink (the better the squarest and flatest) and three screws to attach the Heatsink to the logic board.
2. Mark the holes available around the CPU on the Heatsink.
3. Drill the three holes on the Heatsink carefully, because an error can drive it unusable because of a displaced hole.
4. Apply some thermal grease on the CPU.
5. And attach the Heatsink carefully, tightening the three screws to the logic board trying not to crack the CPU core.

This is how I installed a standart Pentium 4 heatsink and that is how it looks:

 

[maxpayne.co.uk]

Deleted.

 

[wernerru]

Fastest oc so far?

Just curious as to what the fastest everyone's pushed their eMac's so far? i'm still wondering if mine was just a fluke that it took 1.6 from 1.0 without a problem (2nd gen). be cool to see what the different proc's are capable of

 

[shadowmoses]

I think 1.6mhz from 1ghz may be one of the biggest OC's an eMac has seen..

ShadOW 😎

 

[seb_carley]

Just curious as to what the fastest everyone's pushed their eMac's so far? i'm still wondering if mine was just a fluke that it took 1.6 from 1.0 without a problem (2nd gen). be cool to see what the different proc's are capable of

1st post (user since 1997: Newton 120, Performa 5400, iMac indigo 450MHz) Hi all!

Been reading this thread since getting my 3G eMac (1.25GHz 7457 v1.1 (tech 0)) last summer. Had a slow day at work yesterday so I read the entire thread again and looked at leo's site.

Have taken the plunge and removed R270 and R673 (to get to 1.58) with a swiss army knife!

No boot sound - blank screen!

<heart sinks>

cracked open again and removed R689 (for 1.5).
reset PMU.
<prays>

boot sound like music to my ears (so good I zapped PRAM to hear it again🙂)

ATM reports 1.5GHz but kernel panic after 10 minutes. shut down, go for walk, return and boot. So far (30 mins) so good but haven't done anything too proc-intensive yet.

phew!

So now I'm interested in getting a Zalman variable speed fan controller (not too sure how stable it'll be if it runs hotter though), had a look at the site describing how to install and would appreciate anyone who's done it giving a quick english guide (google translation not so good) on how easy this is (preferably with a swiss-army knife 🙂 ).

now to compress some VIDEO_TS...

cheers

 

[madmaxmedia]

Installing the fan is easy, much easier than the work you've already done.

After you get the fan and open your eMac up again, you see pretty easily where you need to shave off a bit. It will take you all of 5 or 10 minutes, I think I used a steak knife.

BTW, when you OC'ed your G3, you didn't have to remove the heat sink or anything right? I'm going to do mine soon as soon as I summon the time and courage. I've already swapped out my HD and optical drive, so disassembling is old hat for me. 😉

 

[maxpayne.co.uk]

Installing the fan is easy, much easier than the work you've already done.

After you get the fan and open your eMac up again, you see pretty easily where you need to shave off a bit. It will take you all of 5 or 10 minutes, I think I used a steak knife.

BTW, when you OC'ed your G3, you didn't have to remove the heat sink or anything right? I'm going to do mine soon as soon as I summon the time and courage. I've already swapped out my HD and optical drive, so disassembling is old hat for me. 😉

You have to remove the logic board, but not the heatsink on the CPU.

BTW, removing the jumpers with the knife probably wasn't a good idea because it may remove the metal track which will disallow you to underclock it again if the system is unstable.

 

[madmaxmedia]

You have to remove the logic board, but not the heatsink on the CPU.

BTW, removing the jumpers with the knife probably wasn't a good idea because it may remove the metal track which will disallow you to underclock it again if the system is unstable.

Thanks for the info.

I didn't use a knife to remove the jumpers, I used it to shave the plug to make the variable fan speed controller fit. 🙂

I'm going to OC my eMac next, but will leave the steak knife in the drawer. 😉

 

[seb_carley]

Thanks for the info.

I didn't use a knife to remove the jumpers, I used it to shave the plug to make the variable fan speed controller fit. 🙂

I'm going to OC my eMac next, but will leave the steak knife in the drawer. 😉

Nah, I think he meant it was a bad idea for me.

As it happens, I just slipped the tip of a blade under the jumpers and popped them off, the silver blobs either side remained intact. (lucky they do, I had another kernel panic and am possibly going to step down to 1.42...)

fun this!

cheers

 

[seb_carley]

You have to remove the logic board, but not the heatsink on the CPU.

Lucky really, I saw two heatsinks, a standard looking black knobbly one (I think on the GPU), and a huge weird (permanent looking) chunk of copper leading to a copper bar/pipe extending past the back of logic board to a series of heat dissipation plates next to the fan.

Never seen much like that before. (but then I never looked).

2rc I had to remove the combo drive, unscrew the logic board mounting, disconnect the video, speaker cables and pull the logic board out - easy. 🙂

 

[seb_carley]

massively unstable

Hi again

System is super unstable at 1.5GHz, have had at least 20 kernel panics since OC yesterday.😱

Picking up a soldering iron tomorrow to take me down to 1.42 but wondered:

Is this likely to be a heat issue? If so what's the best way to install a small fan?

Would adjusting vCore make me potentially more stable at 1.5? If so what jumpers to remove on vCore chip? (i downloaded the pdf)

Come on! Help the stupid!🙂

Cheers

 

[shadowmoses]

Adding more fans is not an option, and i dunno about the vBench scores...
Maybe you should just put it down to 1.42..

ShadOW 😀

 

[seb_carley]

yeah, have now underclocked to 1.42.

with a sooty and bashed piece of crap soldering iron I borrowed from work! and a cup of strong black coffee making my hands shake all over the place(whisky would have been better) 🙂

seems stable enough for now, I think crashes at 1.5 were heat related.

wish me luck.

<edits sig>

 

[madmaxmedia]

How would a 1.42 or 1.5 GHz eMac compare to a 1.6 GHz G5 iMac?

From searching around the web, it seems the G5 is only slightly better per clock cycle than G4 for most stuff. Meaning that a G5 with 10% higher clock speed than G4 will do most things about 15-20% higher (with some variations of course.) That was surprising to me since everyone complains about how slow the bus speed is on the G4's...

I was considering the idea of buying one of the G5 iMac refurbs at Apple.com for $999. But if it's only marginally better than a 1.5GHz eMac then I probably won't bother. The main improvement would be the screen and form factor.

I guess it depends on what EBay value for a 1.5GHz/120GB/512MB/SuperDrive eMac is...

 

[topgunn]

How would a 1.42 or 1.5 GHz eMac compare to a 1.6 GHz G5 iMac?

From searching around the web, it seems the G5 is only slightly better per clock cycle than G4 for most stuff. Meaning that a G5 with 10% higher clock speed than G4 will do most things about 15-20% higher (with some variations of course.) That was surprising to me since everyone complains about how slow the bus speed is on the G4's...

I was considering the idea of buying one of the G5 iMac refurbs at Apple.com for $999. But if it's only marginally better than a 1.5GHz eMac then I probably won't bother. The main improvement would be the screen and form factor.

I guess it depends on what EBay value for a 1.5GHz/120GB/512MB/SuperDrive eMac is...

The greatest difference in speed is found in the GPU, FSB, memory, and SATA not in the CPU. The a 1.5GHz G4 would be similar to a 1.6GHz G5 overall though each has their strong suits. The other features of the iMac would be where it pulls away from the eMac. Though the 1st gen iMac G5 did have the bum SATA controller and now the eMac has a 9600 GPU so the difference between a new eMac and a 1st gen iMac G5 is minimal.

 

[madmaxmedia]

The greatest difference in speed is found in the GPU, FSB, memory, and SATA not in the CPU. The a 1.5GHz G4 would be similar to a 1.6GHz G5 overall though each has their strong suits. The other features of the iMac would be where it pulls away from the eMac. Though the 1st gen iMac G5 did have the bum SATA controller and now the eMac has a 9600 GPU so the difference between a new eMac and a 1st gen iMac G5 is minimal.

Thanks for the scoop! Did you OC yours yet?

I guess I'll still consider the switch, but not for performance. The 17" widescreen LCD sure looks nice... (plus the overall look...)