I used that AMS 460w with dual +12v rails and it seemed to work well. Allowed me to take my SL6XKs all the way to 3206MHz (229x14) Prime95 stable.
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I used that AMS 460w with dual +12v rails and it seemed to work well. Allowed me to take my SL6XKs all the way to 3206MHz (229x14) Prime95 stable.
hey check this psu out! http://www.zipzoomfly.com/jsp/Produc...uctCode=270303
made for xeons and mps 33a on the 12v rail for for 82 bucks!!
i think i may be getting this one...
:toast:
I may just be thinking too much or not thinking enough. :lol: Basically it boils down to "seemed to work well." Whatever works... works. :up:Quote:
Originally Posted by fr0stedflakes
Ok... I'm going to run a single +12v rail 18A power supply in my Xeon rig for a week or so(or until it dies).
After thinking a bit longer about this I have a feeling all the things I've read about having a huge +12v rail for these Xeons may just be a bit too alarmist. Seeing as a rig with two 1.6GHz LV Xeons overclocked to 3.2GHz only pulls ~250w from the wall... I am no longer thinking that you need to have an uber +12v rail.
250w from the wall... that doesn't take into account the power supplies inefficiency... And that draw includes the power needed for the video card, memory, fans, motherboard, and hard drive.
If that 250w was TOTALLY from the +12v rail then that is still only 21A of current. :confused:
Yeah... I think anything in the 18A to 20A range should be fine for pure crunchers. If you start adding loads of hard drives and optical drives then that is where you are going to want a beefier power supply.
I still don't really like the split rails... but after trying to think about it for a bit... I guess they aren't too bad really. :shrug:
How much power does a PC take if ran 24/7? If it's that high...enough to make a HUGE electric bill... AHHH!!!
I am tempted still. And does the Xeon's usually overclock this well?
I believe the second +12v rail on my AMS was almost exclusively dedicated to providing current for the CPUs. IIRC, the wires for the second rail only went to the aux 8-pin connector. Everything else (mobo, molexes, S-ATA power) were on a single +12v.
So I wouldn't be worried at all about these dual +12v supplies not being able to give the CPUs enough amperage, and I think my Xeons at 3.2GHz can attest to that fact. :)
EDIT: A member on the 2CPU.com forums used a Kill-A-Watt meter to test the power consumption of his dual Xeons on the AC side. Here's the thread:
http://forums.2cpu.com/showthread.ph...ht=power+usage
At stock volts, 2.7-2.8GHz is a good bet. 3.2GHz is somewhat typical for the D1 1.6GHz LVs at 1.6v. You're almost guaranteed 3.0GHz, and some of the better chips will do 3.3GHz. It also depends on how much your board undervolts. PC-DLs are notorious for undervolting. During load my Vcore with the 1.6v VID mod would drop to ~1.54v. I've heard of people's PC-DLs going as low as 1.52v. With the full 1.6v, the chips probably could've done 3.3GHz+. This is all with aircooling. WC'g/TEC/(dare I say it) phase should yield even better results, but kind of negates the whole budget factor of the 1.6LVs. If you're going to spend insane money on cooling, you might as well buy some higher-end Xeons, which should be capable of well into 3GHz.
For the C1s, 2.4-2.5GHz is about all they're good for with stock volts. With the 1.6v mod, expect 2.6-2.7GHz.
an A64 pulls about 230Watts from the wall... really close to the Xeons.
just curious what in ur rig? like how many HDs, optical, what kinda video? just to give an idea of how much power ur using upQuote:
Originally Posted by fr0stedflakes
Nothing special other than the Xeons. 6.4gb hard drive, 52x CD-ROM, GF4 MX420, 512mb PC3200, three mid-speed 80mm case fans. The biggest power consumers besides the Xeons were probably the beastly 60x60x38mm fans on my IWTs, lol.
hmm maybe u dont need a ton of wattage....that being said ill probably still go w like a 460watt just to be safe. id rather spend a lil more n do it right the first time. lol i learned this the hard way to many times already :cool:
Wattage doesn't matter - it's where the wattage goes that makes a difference.
I could buy a 700w power supply with 100A on the +3.3v rail... but if it's only rated for 5A on the +12v, it's useless.
So try to get out of the higher wattage = more power mentality. It all depends on how the power is distributed among the rails. In the case of the AMS and Enermax power supplies, it's right were you want it to be for a dually: on the +12v rails.
That 460w Enermax should work fine, I'd definitely get it. Especially if overclocking, you don't want to skimp on the PSU. :)
I was looking at the pin mods here http://www.ctechnet.com/hardware/Asu..._uwire_mod.htm and it doesn't seem like there's a way to give the 1.3V (130nm) CPUs more than 1.6V with the pin mod. Is there a way to get them to run at 1.625V (to make up for the undervolting of the PC-DL)? If there is, would the extra voltage harm the CPUs?
Sorry for asking so many questions, but I figure someone else might be able to use this info, too. Thanks for any help. :)
Oh, BTW, I got that pin mod link from one of the auctions on those 1.3V 1.6GHz Xeons from that eBay seller you linked to, Jeff.
The PC-DL only supports VID settings up to 1.6v. However, you can give the Vcore mod a shot. I believe the voltage regulator on the board will allow a 10% overvolt of the VID pins setting, so that means you could take the Vcore as high as 1.76v (minus w/e your board undervolts). Then you could do the Vdroop mod to compensate for the voltage drop during load. The mod requires soldering to the board, and is a bit more complicated than the Vdimm mod, so if you don't feel comfortable doing this, you might want to ask a friend or someone at an TV/electronics repair shop to do it for you.
You'd definitely want some better cooling than IWTs if you went this route, though. My Xeons would top out at ~56*C at 1.54v actual fully loaded (four instances of P95 max FPU stress). Good watercooling could probably handle 1.6-1.76v. Higher than 1.65-1.7v is really starting to get up there for the Prestonia/Northwood cores, especially considering the speed gains would be minimal. You'd probably be shaving quite a few years off your processors with that much voltage, especially since they will more than likely be running 100% 24/7. It just wouldn't be worth it IMHO.
EDIT: Also came by some SuperMicro heatsinks for $5.99/ea that you guys may be interested in. Don't know how they compared performance-wise to the IWTs, but I've read they're a little quieter. Also am not sure about PC-DL compability. They look like they'd fit.
http://store.yahoo.com/svcompucycle/fan-0042-cf.html
Jeff, have you ever tried to do a VAGP mod. That will make it easier for you to reach high FSB's.
I think I'll attempt an Opteron soon. Let's see which one is faster :)
Opterons will probably blow the Xeons away. Unfortunately, though, they are hella expensive. :(
yeah but they dont have HT, do u think that will effect it?Quote:
Originally Posted by fr0stedflakes
btw u might be interesting in this thread:
http://www.xtremesystems.org/forums/...ad.php?t=50973
new dual opteron board from abit in the same style as the pc-dl no need for registered ram! looks pretty cool.
it will also be interesting to see how the new dual core smithfield cores turn out, since once intel releases the hyper threading version of the smithfield chips it will have 4 virtual cpus just like the xeon, plus since the two cores are on one chip it should be faster then xeons. some cool stuff on the horizon......better start saving up :D
I completely forgot about HyperThreading. :)
That would probably level out the playing field pretty well.
BTW very interesting link on the Abit board. And since it uses the nForce4 chipset, should overclock well.
I dunno. How much does the cheapest Opteron cost? If I can, I'll try to obtain one, or go Xeon.
http://www.newegg.com/app/ViewProduc...roperty&DEPA=1
looks like the cheapest opteron is $155 but its only 1.4ghz seems a lil slow....but amd cpus are supposed to be faster clock for clock then intel so i dono. i have no idea how opterons oc....if at all but that abit board would be the best bet if u wanna try it. probly really expensive tho, might as well go 1.6 lv xeon if ur on a budget(not that they are cheap lol)
do u think ht really matters? i dont really know how it works other then u have two virtual cpus in one, does it just split the power of the one cpu into two so it can better manage multi-tasking? if thats the case then it wouldnt really make much difference when it comes to folding or games or other single process apps.
shadowing if u do get opterons keep us posted id be very interested :D
:toast:
AMDs are faster clock per clock than Intel, but HT does offer a nice performance boost that probably makes up for this.
I am no engineer, so I couldn't even begin to explain how HT works. But from what I've read, it offers around a 20% increase in folding output. So yes, I'd say it's worth it.
Wait until summer... I think i MAY have it ready by then. But I'll keep ya posted on this subject if I do build it. Or there's the fact I might not be able to. Depends of my budget. ;)
thanks i wasnt sure about that, so in that case unless opterons oc like crazy its probly gonna cost a :banana: :banana: :banana: :banana: load to get the same or better performence as the lv xeons.Quote:
Originally Posted by fr0stedflakes
EDIT:cool man it would be neat to see how the two compare, looking forward to seeing what u can put togetherQuote:
Wait until summer... I think i can have it ready by then. But I'll keep ya posted on this subject if I do build it.
I have a hunch that the HT Xeons will wipe the floor with the Opterons in D2OL... especially if you factor in cost. But it's really only a educated guess until someone comes around and proves that statement wrong or right. ;)
100% overclocks on air are a thing of beauty. :up:
That is if you love fan noise ;) I think the Opterons beat the Xeons. I read some reviews on it and it appears the Opteron owned them. There is also the fact that the Opterons distribute load better and etc.