nehemiah faster than 1GHz?

the_smell · Post by **the_smell** » Wed Dec 03, 2003 6:29 am

I remeber many a year ago that via C3 cpu's were going to be made clocked faster than 1GHz, has anyone heard anything about this or is this just a creation of my twisted imagination?

I'd love to be able to have a bit more speed on my 800MHz C3

server, but I'm wondering if moving up to a 1GHz nehemiah will make much difference!

Thanks

Trip · Post by **Trip** » Sun Dec 07, 2003 3:00 am

yeah, they have stuff posted about a 1.2 Ghz and 1.4 all over their website: http://www.viatech.com/en/viac3/c3.jsp

But it hasn't come out yet.

I dunno if it ever will, Intel has them thoroughly whupped with the Pentium M. I read some where of a quad Via C3 board being developed, but it was really more of a rumor than a plan.

Do you run the C3 800 fanless?!

the_smell · Post by **the_smell** » Sun Dec 07, 2003 5:33 am

Thanks for the info Trip...

Yep, I run the C3 800 without a fan, the server box it's in doesn't contain a single fan

The heatsink I use is an old aluminium coolermaster thing with the fan removed. CPU and system temperatures never go higher than room temperature.

Mustn't grumble

silvervarg · Post by **silvervarg** » Sun Dec 07, 2003 1:31 pm

...doesn't contain a single fan...
CPU and system temperatures never go higher than room temperature.

And the conslusion is that the numbers you are reading must be wrong.
You might still have aceptable temps, but you might also be dangerously high.
With low or almost no airflow in the chassi you should get at least a few degrees higher systemp temp than room temp.
A passively cooled CPU certainly has to be a few degrees varmer than the system temp. If the heatsink was exactly the same temp as the air inside your chassi it would not have any cooling effect at all.
Any temps that does not follow this would contradict at least one funtamental physics law.
If you can't get your system to measure temps correctly try other ways to measure temps. E.g. with a normal digital thermometer for outside temperature you can ususally get some idea of the real temps.

ghowarth · Post by **ghowarth** » Sun Dec 07, 2003 5:26 pm

Someone pointed out that the 1.2ghz version is available in Germany. I googled around and found some places in Germany selling them, but not really anywhere else. Dunno why.

Trip · Post by **Trip** » Sun Dec 07, 2003 7:00 pm

ghowarth, do you mind posting a link to somewhere that sells them? Even if they only ship to Germany, that'd be interesting.

Processor Electrical Specifications doesn't even have the 1.2 listed...

the_smell, The 800Mhz C3 you have probably puts out 8.5W max., but could put out up to 12W max. depending on which version you have.

SPCR and pcsilencieux.com(Kostik's site) suggest that 10W can be cooled passively with low airflow and ~20W passively with good case airflow. Both of those figures probably assume a really good heatsink is used with them.

Heat Produced from 1Ghz Nehemiah C3
Processor Electrical Specification: 11.8W typical, 12W max.
Kostik (from Via's information): 11.5w typical, and 15w max.
I dunno which is correct...

Kostik, an SPCR member, attempts to run a Nehemiah 1Ghz fanless and concludes:

"We were not able to cool the Nehemiah passively with no airflow, and considering the temperatures reached, there's little chance that a better heatsink would have been enough. Nevertheless, we were impressed by the temperatures that the C3 can sustain, which makes it the perfect tool for experimenting, without fear of damaging it.

With little airflow, and a low-end heatsink, the C3 is cooled correctly and will work flawlessly. Without a fan, with the PSU as the only source of airflow in the case, it ran stable in our test system during three days."

ghowarth · Post by **ghowarth** » Mon Dec 08, 2003 4:29 am

Here's one I just whipped off google:

www.materiel.net

the_smell · Post by **the_smell** » Mon Dec 08, 2003 5:04 am

Again thanks for the good info on the 1.2Ghz chip, I might just try and get me one of them and try using a copper flower cooler with it.

silvervarg you quite rightly pointed out that my temperature readings must be wrong. I agree - my CPU motherboard always reads 15 degrees C after a good few days with the computer turned on, this seems a little low. So I rigged up a digital thermometer from the lab I work in in the day time and took some readings, I also used my Lian Li thermometer from my other computer to get a second opinion. However readings at the base of the heat sink were always in the 18-21 degrees range.

This is probably because I've positioned the computer to allow a bit of convection cooling... The case is behind a desk with the front facing the coolest corner of the room (in winter it averages about 15 degrees). The rear in which the hotter components (CPU, PSU and VGA) at situated point towards a warmer area (23-25 degees typically), especially when I have my other computer on as it pumps out heat behind the desk - it helps to keep my feet warm

. So I think the cool air must be drawn though the front of the case providing sufficient flow to cool it down - I think I might have to invest in a few fans before the summer arrives!

I hope that wasn't too confusing.

Trip · Post by **Trip** » Mon Dec 08, 2003 7:32 am

Be sure and post if one of y'all finds a place that ships to America.

pangit · Post by **pangit** » Tue Dec 09, 2003 12:56 am

I recently built a C3 machine for my Dad's home office, and that runs a C3 800MHz Ezra with just a passive bog standard aluminium heatsink on it. The only fan in the entire case is a very quiet and low airflow one in the PSU, which draws enough air over the heatsink. It never goes above 45*C.

Can't comment on the Nehemiah though!

silvervarg · Post by **silvervarg** » Tue Dec 09, 2003 7:35 am

Pangit:
Can't comment on the Nehemiah though!

According to Processor Electirical Specifications the max power dissipation is:
800MHz depends on what core and vcore it uses. 18.5-19.4W seems normal.
1GHz Nehmiah 12W.

Even at 19.4W with a simple aluminium heatsink you need only a little airflow to get enough cooling.

Trip · Post by **Trip** » Tue Dec 09, 2003 8:32 am

Via C3-800T runs cooler. The Samuel 2/Nehemiah/Ezra-T run hotter than the Ezra/Ezra-T

Scroll down all the way to the bottom for the Via chart: http://users.erols.com/chare/elec.htm

I dunno what's available and what's not, but the chart may help you out. (notice the missing 1.2Ghz Nehemiah)

Also, Kostik wrote in his review that the nehemiah 1Ghz put out 15W max. Either he or the chart is wrong.