I want to make a folding farm... I have one already but i want to go caseless
has anyone ran 2 x K7D's off 1 PSU ? if so what PSU handels this ?
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Comments
Straight_ManGeeky, in my own wayNaples, FLIcrontian
edited May 2004
700-800 W with CD drives, reasonable HDs, to post both reliably. Try two 300-350 W PSUs instead, the wattage I am talking is industrial PSU supply wattage if from a single PSU.
with few devices in the two systems, it would probably work with far less than 700 to 800 watts. probably 400 to 500w. especially if you don't boot them both at the exact same time. with atx, though, it will be interesting to hook one psu up to two motherboards. the motherboard turns the psu on via the atx connector, so i don't know how you would deal with that. maybe there's some article on how to do this that you've read and i haven't...
Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
Running multiple boards off 1 PSU is an extremely bad idea. I can't really explain why, as I don't know enough about electronics (computers and electronics are two totally different things), but I've talked to some electrical engineers about it, and they all said, rather emphatically, I might add, not to do it. It has something to do with feedback or something...
Hi Shroomer, nice to see you. I would think it would take a pretty hefty psu to handle 2-K7D boards with high clocked Bartons, but I think it's doable. I would think that an Antec TrueControl or TruePower 550 or Enermax 651-PVE or PP&C Turbo Cool 500 would be needed to do it reliably.
One of the reasons for doing this is for power. When you get a lot of machines, the cost of electricity becomes huge and this is a way to save some power.
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Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
mmonnin, how does this save power? You've got 2 systems running off 1 PSU. You'll use effectively the same amount of power as 2 systems with 2 power supplies.
It should pull less power than 2 PSUs. Plus it will produce less heat with one PSU. Heat is another major issue with a large farm.
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Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
Not necessarily. Say each system draws 300w. You can run 2 300w PSUs, or 1 600w PSU. If they've got the same efficiency, then you're going to be drawing just as much power, and generating just as much heat, with 1 PSU as you will with 2.
probably 2400 mp's in all sockets and no real oc well if they do it will be at stock vcore so load on the psu will be minimal... i will use a CD drive to setup the HD's with drivers/os ect... in a single board/psu config before moving it all to 2 boards on a singel PSU
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Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
And you're willing to risk killing all that hardware to save a few $$ on PSUs?
I just dont see how it is not posiable i have 1 K7D as described above with a CD drive and 2 80mm tornado's all running with a 350W Powmax PSU and it has been running for about a year with NP's
less heat and space in the custom case that holds all the parts
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Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
I'm telling you, it doesn't generate less heat, and here's why:
Say each system draws 200w. You put them on 2 separate, 300w PSUs.
Each PSU has an efficiency of 90%- 9 of every 10w of input power goes out as dc; the other 1 goes out as heat. Each PSU would dissipate 20w of heat- for a total of 40w.
Now say you buy 1 550w PSU that also has an efficiency of 90%- the heat output will still be 40w, it'll just be coming from 1 PSU instead of 2.
with a more efficient PSU it would be less heat...
space and outlets is the main reasons and also being the first to do it would be nice
I still think this will draw less power than 2 PSU's also... you cant tell me that 2 psu's with no load vs 1 with no load will not be a diferance on a power bill so 1 PSU should be more efficient
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Geeky1University of the Pacific (Stockton, CA, USA)
edited May 2004
It won't draw any less power, as I explained above; a bigger PSU is not inherently more efficient than a small one.
Somebody did this but I can't remember where I saw a link for it. I'll do some looking...
//edit: 30 minutes of seaching and I can't find it. The best I can remember, the guy had a bunch of motherboards sitting on shelves (no cases). It was two motherboards and one psu per shelf. Man, I wish I could find that link!
Looks like the links in mmonnin's post does show how to do it though...
Rather than getting crappy, cheap PSUs that most likely will have poor efficiency he could get a bigger better more efficient PSU that would put less heat. A higher quality PSU will be more efficient like an Antec or PC Power&Cooling.
yeah great PSU's for a PC will run about 70% max on efficiency. I still think i will give this a try soon with 2 that I have and if it works out i will start the farm up... I have a Antec TC 550 right now I guess I can try with this PSU...
would it be safe to say if the rails on the mobo's (both) on a TC 550 are better than what I have on my Powmax 350 now then i will be good to go ?
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LeonardoWake up and smell the glaciersEagle River, AlaskaIcrontian
edited May 2004
It is possible. Yes Bill, I remember seeing what you're talking about. The pic below shows 24 motherboard/CPU units. If you look at the stack of power supplies in bottom left, it would appear that there are about 12 or so (accounting for what apparently is not visible). BTW, the rig shown is a distributed computing platform, for which program I don't know.
yeah great PSU's for a PC will run about 70% max on efficiency. I still think i will give this a try soon with 2 that I have and if it works out i will start the farm up... I have a Antec TC 550 right now I guess I can try with this PSU...
would it be safe to say if the rails on the mobo's (both) on a TC 550 are better than what I have on my Powmax 350 now then i will be good to go ?
After having to install a 2nd A/C in my shed this summer and seeing the last electric bill I was thinking of converting some of these to run 2 mobo's per PSU--> http://home.austin.rr.com/skipsjunk/cjunk/texascrunch2.html. The pic is a little dated, I added another 'backet cruncher' and it's now two stacks of 3.. with the 7th one to go in soon. I already had a bunch of these baskets because they were the kids toy storage years and years ago. Had to do something with them ;-)
Looking at "advertised" max current draws it looks like a better solution might be to downsize to the smallest PSU that runs the mobo effectively. I say that because you can find sub-235w PSUs with a max input current of 3-4 amps. The 250-300w PSUs typically have a max current draw of 7-10 amps. Figure running normal running they draw about half of that or less. I need to borrow a good inductive current meter.
So, anyway, I've been buying old used (but tested) GoodWill store PSUs in the 140~200w range for $9 each. They run OC'd Barton core K7s just fine with the CPUs at 100% 24/7/365.
BTW, My UPS units say that my "basket" computers draw about 110w each. But I have some doubts about the accuracy of those numbers. But I'm sure it would be an easy load to run two of these off a reasonable quality 300~350w PSU. But I want to take some actual current readings on my 350w PSUs vs my 'Goodwill" PSUs to see what the actual wall current draw is.
My 'basket crunchers' consist of a mobo, CPU, HSF, 1 HDD, on board video and either on board LAN or PCI lan card. No floppy, no CD, no kybd or monitor. All the components are plastic wire-tied to the basket. Originally thru KVM switches but now using RealVNC. -- Skip
Comments
I found a link on the community awhile back with a few links to PSU mods.
http://forum.folding-community.org/viewtopic.php?t=6756&highlight=service
Here are some of the links on that page:
http://shockclan.hopto.org/folding/psu1.html
http://shockclan.hopto.org/folding/psu2.html
http://forums.extremeoverclocking.com/showthread.php?s=&threadid=33884
do you have some data to back that up...i may be interested in doing something if so.
just a small 3.3 Gb HD on each
probably 2400 mp's in all sockets and no real oc well if they do it will be at stock vcore so load on the psu will be minimal... i will use a CD drive to setup the HD's with drivers/os ect... in a single board/psu config before moving it all to 2 boards on a singel PSU
I understand caseless but why one psu? Buy a 15 buck 500 watt off ebay.
Tex
Say each system draws 200w. You put them on 2 separate, 300w PSUs.
Each PSU has an efficiency of 90%- 9 of every 10w of input power goes out as dc; the other 1 goes out as heat. Each PSU would dissipate 20w of heat- for a total of 40w.
Now say you buy 1 550w PSU that also has an efficiency of 90%- the heat output will still be 40w, it'll just be coming from 1 PSU instead of 2.
space and outlets is the main reasons and also being the first to do it would be nice
I still think this will draw less power than 2 PSU's also... you cant tell me that 2 psu's with no load vs 1 with no load will not be a diferance on a power bill so 1 PSU should be more efficient
//edit: 30 minutes of seaching and I can't find it. The best I can remember, the guy had a bunch of motherboards sitting on shelves (no cases). It was two motherboards and one psu per shelf. Man, I wish I could find that link!
Looks like the links in mmonnin's post does show how to do it though...
And its no where near 90% anyway.;)
would it be safe to say if the rails on the mobo's (both) on a TC 550 are better than what I have on my Powmax 350 now then i will be good to go ?
After having to install a 2nd A/C in my shed this summer and seeing the last electric bill I was thinking of converting some of these to run 2 mobo's per PSU--> http://home.austin.rr.com/skipsjunk/cjunk/texascrunch2.html. The pic is a little dated, I added another 'backet cruncher' and it's now two stacks of 3.. with the 7th one to go in soon. I already had a bunch of these baskets because they were the kids toy storage years and years ago. Had to do something with them ;-)
Looking at "advertised" max current draws it looks like a better solution might be to downsize to the smallest PSU that runs the mobo effectively. I say that because you can find sub-235w PSUs with a max input current of 3-4 amps. The 250-300w PSUs typically have a max current draw of 7-10 amps. Figure running normal running they draw about half of that or less. I need to borrow a good inductive current meter.
So, anyway, I've been buying old used (but tested) GoodWill store PSUs in the 140~200w range for $9 each. They run OC'd Barton core K7s just fine with the CPUs at 100% 24/7/365.
BTW, My UPS units say that my "basket" computers draw about 110w each. But I have some doubts about the accuracy of those numbers. But I'm sure it would be an easy load to run two of these off a reasonable quality 300~350w PSU. But I want to take some actual current readings on my 350w PSUs vs my 'Goodwill" PSUs to see what the actual wall current draw is.
My 'basket crunchers' consist of a mobo, CPU, HSF, 1 HDD, on board video and either on board LAN or PCI lan card. No floppy, no CD, no kybd or monitor. All the components are plastic wire-tied to the basket. Originally thru KVM switches but now using RealVNC. -- Skip