How many watts do I REALLY need?

Sunfox · Post by **Sunfox** » Fri Aug 12, 2005 2:20 am

Looking up upgrade my computer to the following specs:

Intel P4 3.73 Extreme
4GB memory
ATI X850XT PE
4 x HDD in RAID (so they'll be operating concurrently)
3 x DVD
3 x add-in cards
probably 5 total fans (2 or 3 x 120mm case, CPU + extra video)

...And I'm a bit confused as to how much power I'll *really* need. I'm currently using a SilentX 450w supply and have no qualms about it, but will that be enough for these kind of specs? My concern is caused by having a power-hungry CPU, power-hungry video card and then topping it all off with 4 hard drives.

Edit: Can't believe the topic said "watta" for a whole day...

t1000 · Post by **t1000** » Fri Aug 12, 2005 2:53 pm

If someone here tells you an Antec Phantom 350 will do for your rig I'm going to finally go out and buy one.

1000

~El~Jefe~ · Post by **~El~Jefe~** » Fri Aug 12, 2005 3:11 pm

well um. if i had that system id shoot myself in the head for not getting an fx-57 and a 7800 GT.

dood, youll blow big chunks of wattage for less power.

is this a gaming rig or a home video thing?

I'm going to tell you that a socket 754 with max cpu in it does equal or better to this in speed on every site i looked up. that chip is 280 dollars shipped. also, you will be using a lot of wattage and heat for nothing. I dont recommend 754 obviously, but really dood, this go fx 55 or 57 if you want gaming power and also a coolish chip when not gaming.

this is obviously not a silent rig and so, a seasonic 430 will do this more than fine. I wouldnt bother with antec phantom, your psu will roast marsmallows, so will your gfx card, its like a summertime clambake fiesta going on in that case.

cotdt · Post by **cotdt** » Fri Aug 12, 2005 4:01 pm

I'm with ~El~Jefe~ on this one.

Yes, Phantom 350 will easily take that rig. I had a similar rig to that that one, with a 4GHz Prescott, 6800GT and 6 hard drives, and the Seasonic Super Tornado 300 took it just fine, with very stable voltages I might add. I doubt that computer even eats up 220W. People often recommend high wattage PSU's because they see 500W generics not even handle 150W. However, any high quality name brand PSU of any wattage will do.

~El~Jefe~ · Post by **~El~Jefe~** » Fri Aug 12, 2005 4:53 pm

ah yes, ok, good recommendations yes.

the other thing you cause me to add is this: the phantom IS enough to do all of that.

the x800 series is a mental thing, it really does not use more power than the 9000 series, actually the x800 XT uses LESS power than a 9800 XT, one is a gerbil on crack, the other one is a tiger chilling out, one is more efficient than the other one.

just go get a fx57... i want someone to have one if it's not goign to be me... and it's NOT

Pentium EE at that speed is also manufactured by a company named Delongi, they make space heaters.

Sunfox · Post by **Sunfox** » Sat Aug 13, 2005 12:18 am

Sorry, I'm not doing AMD or NV at this stage... this is primarily a business machine for HDTV video editing, so Intel's going to be the thing.

Yes, I fully agree that Intel's current CPU selection sucks compared to AMD for numerous reasons, but in the business world Intel still has a couple few things going for it. Basically I want rock-solid stability. And as for ATI, I get the cards to test so I have to stick with what I've got there.

At any rate, more detailed specs would be:

Intel P4 3.73GHz EE
4gb Crucial Ballistix PC5300 DDR2
Intel D955XBK
ATI X850XT PE PCI-E
4 x Seagate 400GB SATA
Soundblaster Audigy 2 ZX
ATI TV Wonder Elite
Generic SCSI card
1x CD-RW, 1x DVD-ROM, 1x DVD-RW
Zalman CNPS7700-Cu
Zalman ZM80D-HP + ZM-OP1
Antec P180 Case
...plus a boatload of USB stuff.

Most of this has already been purchased, I'm mainly waiting on the CPU and trying to decide on a power supply.

I've decided that I'm going to try to keep the crucial bits of my current system intact (since it's 110% rock solid - another Intel rig), so I prefer to leave its PS in it... which means I am going to need to purchase something new.

And hey, I do like performance served up as quiet as possible... so I'm thinking between the Seasonic S12-500W, and the Phantom 500. My main concern with the Phantom 350 is this system might be pushing it past the halfway point and potentially towards the "warmer" side of things, with no fan backup. Also, I'm not sure I can guarantee getting an 05 version from the place I purchase, while I think all of the 500's are guaranteed the good version.

And to think I scrapped getting an 840 EE for heat and power consumption reasons.

qviri · Post by **qviri** » Sat Aug 13, 2005 1:01 am

Dude, there's no way you'll hear the Seasonic S12 over the four 400GB hard drives anyway, so save yourself the money and forget the Phantom.

Also, AMD's not stable? First time I heard that, but if you say so...

Sunfox · Post by **Sunfox** » Sat Aug 13, 2005 2:56 am

I'm not saying AMD's unstable, but I'm saying Intel is a known stable environment for me and my work. Every time I've gone elsewhere I've ended up with some problem or another. And after an especially hellish time on my last computer troubleshooting a random rebooting problem I swore I wouldn't go elsewhere... but that's a moot point since choosing a platform is not why I'm here.

Ignoring the noise and cost issue, which is the better *power supply*? Or are they somewhat equal?

Post by **NeilBlanchard** » Sat Aug 13, 2005 6:10 am

Hello,

The recommended PS section is where to look -- an S12- 430watt SeaSonic would be pretty ideal!

eMadman · Post by **eMadman** » Sat Aug 13, 2005 7:27 am

If you want to do video editing, you might be better off running the dual core EE processor intel has out. It should cost you about the same and you'll be able to crank quite a bit more performance out of it if the application supports multiprocessing or hyperthreading.

kesv · Post by **kesv** » Sat Aug 13, 2005 9:03 am

eMadman wrote:If you want to do video editing, you might be better off running the dual core EE processor intel has out.

Even the plain 3.2Ghz Pentium D should do better at video encoding then the single core P4 EE.

In fact what is truly interesting is that the plain dual core even beats the EE dual core according to these benchmarks:
http://www.anandtech.com/cpuchipsets/sh ... i=2388&p=9

Apparently hyperthreading does not help performance in video enconding benchmarks.

Sunfox · Post by **Sunfox** » Sat Aug 13, 2005 1:08 pm

Yes, the dual wouild do better performance wise, but everything I've read says that thing puts out a LOT more heat than even the 3.73. I don't think I want to have to deal with cooling one.

~El~Jefe~ · Post by **~El~Jefe~** » Sat Aug 13, 2005 4:38 pm

"Basically I want rock-solid stability. "

then you must be going amd venice core right?

no? well intel is NOT more stable at all. No way it is. thats marketing crap that has you hook line and space heater.

if you want perfect stability and great performance get a venice with a top manufacturer, and a board that has been out a year.

Business uses? try the dual core for 400 dollars. it will do everything better than an intel, use no power, multitask and encode faster and be 300% cheaper in total (at least)

im going to spew chunks if you actually buy a 3.73 EE. it does jack dood, get a 2.1+ ghz centrino if you want solid stability and a fast machine, at least its a superior and tried and true chip (pIII tualatin with a kick, many years old now)

*holds his mouth in anticipation*

eMadman · Post by **eMadman** » Sat Aug 13, 2005 10:09 pm

Sunfox wrote:Yes, the dual wouild do better performance wise, but everything I've read says that thing puts out a LOT more heat than even the 3.73. I don't think I want to have to deal with cooling one.

My bro's X2 4200+ runs at about the same temps as my 3500+ venice. Under stress, his heats up a bit more, but the stock heat sink on the 4200+ is also much larger and contains heatpipes which probably help keep the temps as low as they are (low 40's to mid 50's on stock cooling in a stock Sonata II case)

cotdt · Post by **cotdt** » Sun Aug 14, 2005 12:34 am

Yeah, the prescott's are the least reliable of CPU's due to overheating issues with many coolers.

Devonavar · Post by **Devonavar** » Sun Aug 14, 2005 11:55 am

Please keep this thread on topic. The AMD vs. Intel debate has been carried out much more completely and intelligent elsewhere. Please just answer his question: How much power does he need?

Now, back on topic:

Intel P4 EE 3.73: about the same as a P4 670 ... Hot. Can't find TDP at the moment, but according to CPUHeat the maximum theoretical heat dissipation is ~148W (vs. 151W for P4 670). Intel's official TDP spec is lower, probably by ~25-40W. See other comments in this thread for better recommendations for a Video work CPU. All CPU power comes from the +12V rails.

4GB RAM: ~ 20W (but not on the +12V rail, so pretty much irrelevant. Generally, the only rail that matters when sizing a power supply is the the +12V rail)
X850XT: ~72W (mostly on the +12V rail)
4xHDD: estimate ~ 15W each on the +12V rail at spin up ... this is very conservative. (~7W each on the +5V rail). ~6-7W each during seek.
3xDVD: Are you using these simultaneously? If so, ~20W each while burning. ~1W otherwise.
3xAdd-in cards: Depends a little on what they are, but unlikely to draw much from +12V. Usually in the 10W-15W range across all rails, but mosly on the +5V and +3.3V rails.
Fans: ~10W (if that)
Motherboard: ~10W (+12V)

So, adding up the +12V rail, you need ~300W (for a brief second) at startup, or a total of 25A across both rails. Most PSUs can handle this load. At idle, your power requirements will be MUCH lower, in the ~100W range. At full CPU load (for encoding) you are likely to see +12V total in the ~200W range (16A). Gaming will probably be similar (but it's a more dynamic load, so peaks may be higher). Burning DVDs will likely consume ~140W (11A) on the +12V line if all burners are in use simultaneously.

To sum up, the highest power draw you are likely to see is a short peak at startup (or maybe while gaming). I'd aim for a total combined amperage of ~24A across the two +12V rails. This puts you in the 350-400W range as long as you have a modern (ATX12V 2.x) power supply. Your SilenX is not ATX12V 2.x compliant and has a +12V max of 22A.

I would recommend replacing the PSU, if only because you'll need to use adaptors to connector the 24-pin motherboard connector and the PCI-e connector on your VGA card. I real usage, you're PSU may be able to handle a 24A peak at startup, but you won't know for certain unless you actually try it. It may work, but it will be struggling, and stressing it regularly by turning it on and off may be a recepie for a shortened lifespan for the PSU. If you really do count reliability as the highest priority, a good quality power supply may be a good investment.

Sunfox · Post by **Sunfox** » Sun Aug 14, 2005 8:16 pm

Thanks for the detailed response... and thanks for the link to that site as well. Looks like my current CPU takes 95w, the 3.46 I was considering would have taken 126w, and the 3.73 is up there at 148w. Too bad they don't rate the 8xx series yet.

In terms of connectors, the motherboard has a 24-pin ATX, 6-pin 12V plus a molex connector and gives instructions on what to do if you have 20-pin or 4-pin connectors (and includes a 4 to 6 pin adaptor). The video card also comes with a molex adaptor.

Devonavar · Post by **Devonavar** » Sun Aug 14, 2005 8:25 pm

One word of caution about the CPUHeat ratings. Because they are based on theoretical maximums, not real-world usage, they tend to be higher than is realistic. This is Intel's argument for listing TDP instead of "Maximum Power". I leave it to you to decide whether or not Intel is on to something, but it certainly can't hurt to over-estimate. You can check out this thread for more information about MP vs. TDP.

If you want a roughly comparable power number for the Pentium D processors, try looking up TDP on Intel's web site. It may take some digging, but it is listed somewhere. IIRC, they come in at 130W TDP vs. 115W for the higher clocked 6xx series.

From the sound of it, your SilenX is ATX12V 2.x compliant, unlike the model that I found on the internet. Try checking whether or not it gives ratings for two separate +12V rails or not, and what they are.

Sunfox · Post by **Sunfox** » Sun Aug 14, 2005 8:39 pm

No, those were the new motherboard's connectors; the SilentX does indeed only have one 22A 12V rail.

So, I guess I will get something new.

Devonavar · Post by **Devonavar** » Sun Aug 14, 2005 8:50 pm

Oops, looks like I read your first reply too quickly.

Shining Arcanine · Post by **Shining Arcanine** » Mon Aug 15, 2005 2:18 pm

Sunfox wrote:Looking up upgrade my computer to the following specs:

Intel P4 3.73 Extreme
4GB memory
ATI X850XT PE
4 x HDD in RAID (so they'll be operating concurrently)
3 x DVD
3 x add-in cards
probably 5 total fans (2 or 3 x 120mm case, CPU + extra video)

...And I'm a bit confused as to how much power I'll *really* need. I'm currently using a SilentX 450w supply and have no qualms about it, but will that be enough for these kind of specs? My concern is caused by having a power-hungry CPU, power-hungry video card and then topping it all off with 4 hard drives.

Edit: Can't believe the topic said "watta" for a whole day...

I'd say 250 watts tops. Just be sure to watch the ampage.

Sunfox wrote:Sorry, I'm not doing AMD or NV at this stage... this is primarily a business machine for HDTV video editing, so Intel's going to be the thing.

Yes, I fully agree that Intel's current CPU selection sucks compared to AMD for numerous reasons, but in the business world Intel still has a couple few things going for it. Basically I want rock-solid stability. And as for ATI, I get the cards to test so I have to stick with what I've got there.

At any rate, more detailed specs would be:

Intel P4 3.73GHz EE
4gb Crucial Ballistix PC5300 DDR2
Intel D955XBK
ATI X850XT PE PCI-E
4 x Seagate 400GB SATA
Soundblaster Audigy 2 ZX
ATI TV Wonder Elite
Generic SCSI card
1x CD-RW, 1x DVD-ROM, 1x DVD-RW
Zalman CNPS7700-Cu
Zalman ZM80D-HP + ZM-OP1
Antec P180 Case
...plus a boatload of USB stuff.

Most of this has already been purchased, I'm mainly waiting on the CPU and trying to decide on a power supply.

I've decided that I'm going to try to keep the crucial bits of my current system intact (since it's 110% rock solid - another Intel rig), so I prefer to leave its PS in it... which means I am going to need to purchase something new.

And hey, I do like performance served up as quiet as possible... so I'm thinking between the Seasonic S12-500W, and the Phantom 500. My main concern with the Phantom 350 is this system might be pushing it past the halfway point and potentially towards the "warmer" side of things, with no fan backup. Also, I'm not sure I can guarantee getting an 05 version from the place I purchase, while I think all of the 500's are guaranteed the good version.

And to think I scrapped getting an 840 EE for heat and power consumption reasons.

Nice parts. You might want to consider holding out on the audio card (if you haven't brought it already). Creative is coming out with X-Fi audio cards soon and they blow the Audigy 2 ZS out of the water.

By the way, you might want to consider buying Western Digital 400GB hard drives instead (if you haven't already). They should be quieter than the Seagates and have higher performance.

qviri wrote:Dude, there's no way you'll hear the Seasonic S12 over the four 400GB hard drives anyway, so save yourself the money and forget the Phantom.

Also, AMD's not stable? First time I heard that, but if you say so...

I can hear my 17.6 dB Nexus Real Silent Case Fan over my 21 dB Western Digital 320GB Caviar hard drive. I see no reason why he couldn't hear the Seasonic S12 over his four 400GB hard drives (besides the fact that each one alone is louder than mine and there are four of them)

qviri wrote:Dude, there's no way you'll hear the Seasonic S12 over the four 400GB hard drives anyway, so save yourself the money and forget the Phantom.

Also, AMD's not stable? First time I heard that, but if you say so...

Their processors are okay. It is the chipsets that have problems.

Sunfox wrote:I'm not saying AMD's unstable, but I'm saying Intel is a known stable environment for me and my work. Every time I've gone elsewhere I've ended up with some problem or another. And after an especially hellish time on my last computer troubleshooting a random rebooting problem I swore I wouldn't go elsewhere... but that's a moot point since choosing a platform is not why I'm here.

Ignoring the noise and cost issue, which is the better *power supply*? Or are they somewhat equal?

The fanless one will always be quieter.

Although to be honest, you might want to go with the Antec Phantom 500. It is slightly more efficient than the Antec Phantom 350. Don't expect its fan to go on in your P180 case unless something is seriously wrong with your PC's temperatures.

NeilBlanchard wrote:Hello,

The recommended PS section is where to look -- an S12- 430watt SeaSonic would be pretty ideal!

If you're going to be recommending a Seasonic, why are you recommending the 430 Watt one? The 330 Watt one should be able to provide more power than he needs.

kesv wrote:
eMadman wrote:If you want to do video editing, you might be better off running the dual core EE processor intel has out.
Even the plain 3.2Ghz Pentium D should do better at video encoding then the single core P4 EE.

In fact what is truly interesting is that the plain dual core even beats the EE dual core according to these benchmarks:
http://www.anandtech.com/cpuchipsets/sh ... i=2388&p=9

Apparently hyperthreading does not help performance in video enconding benchmarks.

That is due to the fact that it was designed with yields as the number one design priority. Hence, why Intel's processors barely use any additional transistors for HT and generally get a 10% performance boost while IBM's processors use many additional transistors for SMT and get a 40% performance boost.

Vulcan · Post by **Vulcan** » Mon Aug 15, 2005 3:59 pm

I can't belive you guys think this rig would be okay on a 350w phantom. Thats just insane. The minimum I'd use for something this power hungry would be a 450w+ fortron, antec or seasonic (or similar).

qviri · Post by **qviri** » Mon Aug 15, 2005 4:03 pm

Why would it not be? The Phantom is rated for 350W for a reason...

cotdt · Post by **cotdt** » Mon Aug 15, 2005 4:12 pm

My Phantom 350 can supply 500W. I've tested it with special equipment. Its 12V rail can supply 34 amps.

Vulcan · Post by **Vulcan** » Mon Aug 15, 2005 4:17 pm

cotdt wrote:My Phantom 350 can supply 500W. I've tested it with special equipment. Its 12V rail can supply 34 amps.

The 500w phantom and 350w phantom have the same internals AFAIK. However, I would never run a Phantom 350 with that kind of load without a fan.

StarfishChris · Post by **StarfishChris** » Mon Aug 15, 2005 5:13 pm

The Phantom 350 can provide enough power for that. But can it do it without overheating? Let's say that system eats up 200W at load - not unreasonable. (Note about hard drives: they only suck power when spinning up, so as long as the PSU can deliver the power it doesn't matter if it can maintain it heatwise for any length of time.)

(Pout / Eff) - Pout = Pwaste
(200 / 0.86) - 200 = 33 W

With a case fan installed it shouldn't be a problem. Create good case airflow where the air isn't too warm next to the PSU and you should be fine. Three 120mm case fans will be quieter when undervolted but two are sufficient.

However... I don't think an S12 will be audible over four hard drives. If it can deliver the peak power when those discs spin up, go for the 330W. If not, the 380W is certainly enough.

(As for 12v@34A, that means at least 70W of heat! Strap a fan to the PSU before trying that one out, or better still, don't use the monster that draws that much power)

Vulcan · Post by **Vulcan** » Mon Aug 15, 2005 5:42 pm

StarfishChris wrote:However... I don't think an S12 will be audible over four hard drives. If it can deliver the peak power when those discs spin up, go for the 330W. If not, the 380W is certainly enough.

My S12 is basicly silent (with all other fans off/stoped) unless I have my ear right on it, but perhaps theres just too much background noise for me to notice. I don't see the point of a fanless power supply when your going to have other fans in the system. Kudos to anyone what manages to build a pasivly cooled performance system.

Sunfox · Post by **Sunfox** » Mon Aug 15, 2005 7:35 pm

I'll probably go for the Phantom 500 (like I said, I can get Antec stuff easier than Seasonic - my local price on the Phantom ends up about the same as having to mail order the Seasonic), and I do plan on having a fan run in the P180's lower cavity, so it should stay cool enough.

And I don't think we should forget that noise is cumulative. One cricket chirping will be "quieter" than 100, so I don't see why toning down ANY noise generating piece, no matter whether it is theoretically already "quieter" than some other parts, could be a bad thing!

Like I said, I'm happy with "quiet" rather than "silent", but I want as "quiet" as possible.

Shining Arcanine wrote:Their processors are okay. It is the chipsets that have problems.

That's usually where I end up having problems.

Shining Arcanine wrote:You might want to consider holding out on the audio card (if you haven't brought it already). Creative is coming out with X-Fi audio cards soon and they blow the Audigy 2 ZS out of the water.

Yeah, I've been following these closely... problem is while they're advertising X-Fi like there's no tomorrow, I haven't seen ANY indication of when they're actually coming out. And I'm getting tired of going to their site and seeing that "new" information will be coming out in 24 hours... which turns out to be useless.

Shining Arcanine wrote:By the way, you might want to consider buying Western Digital 400GB hard drives instead (if you haven't already). They should be quieter than the Seagates and have higher performance.

I've actually had the Seagates for some time now, since before the WDs were announced. This PC was supposed to have been built months ago, but the motherboard took forever to come out.

Charli Mopps · Post by **Charli Mopps** » Tue Aug 16, 2005 6:19 pm

Ok, no one has mentiont his so I'm going to:

If you're PSU can't handle the load and shorts itself, it may take your Motherboard with it. And YES I have had it happen to me. The PSU blew 3 MBs before I figured out what was going on.

So, given that, I'd say go with a good quality 400-500 Watt PSU
Yes, you could probobly get away with less... but why bother? A 400 Watt Antec is pretty cheap if you get it online. Anyway, nice PSU are nearly silent. I have a 450 that makes very little noise.

sthayashi · Post by **sthayashi** » Tue Aug 16, 2005 6:31 pm

Charli Mopps wrote:Ok, no one has mentiont his so I'm going to:

If you're PSU can't handle the load and shorts itself, it may take your Motherboard with it. And YES I have had it happen to me. The PSU blew 3 MBs before I figured out what was going on.

So, given that, I'd say go with a good quality 400-500 Watt PSU
Yes, you could probobly get away with less... but why bother? A 400 Watt Antec is pretty cheap if you get it online. Anyway, nice PSU are nearly silent. I have a 450 that makes very little noise.

That IS good advice, but around here, we actually don't recommend any "cheap" power supplies. The only things we recommend are ones that MikeC or Devon have personally tested at frighteningly high loads. That combined with measuring their outputs at said loads. That combined with dozens of real world system power draw measurements, we've established that almost any modern 300-400W PSU will power virtually any non-SLI setup.

On the flip side though, Wall power has the ability to smoke a PSU and sometimes by extension a motherboard.