to powerfull PSU?

saltydog806

Is there such a thing as to much power for a system? I’m building a new system, however it is just a stop gap measure in order to upgrade from my off the shelf unit until I can get what I want. My thought is that I don’t want to buy a PSU now only to have to buy another in 6 months. I can only put this in terms I know. If you buy an ac/heating unit for your home and it is oversized you waste money on the unit ,it doesn’t work as efficiently and it can burn itself out faster. I don’t know if the same applies to PSU’s. So far this is what I’m looking at for the temporary new system. I used a calculator at ASUS and it indicated I would need a 550 watt PSU (nothing on what on each rail) so I figure add 10% and go with a 600 watt. However if I calculate the rig I will be upgrading to I believe I will need around 750 watts. So will it hurt anything other than my wallet if I get a 1000 watt now?

1. Case - Thermaltake Armor VA8003BWS Full Tower Case HAVE
http://www.microcenter.com/single_pr...uct_id=0241892


2. MOBO - GIGABYTE ga-p35-ds3r (or similar)
http://www.mwave.com/mwave/Skusearch...iteria=BA23890

3. CPU - Intel core 2 duo 6300 HAVE

4. Memory - PC2-6400 (DDR800), 4-3-3 or 4-4-4 latency.

5. VGA - Don’t know probably a midrange PCI E-16 I don’t know if it will be SLI or Crossfire.

6. Card reader HAVE

7. One internal SATA hard Drive. HAVE

8. One CD-DVD-R-RW drive HAVE

9. One CD-DVD-R drive (?)

Leonardo

1000W PSU for a computer is essentially rediculous in my opinion, unless something like this:

4 X 8800GT
4 X HDD running in RAID
2 X optical DRIVE
dual monitors
CPU overclocked to the max running full load

....all of the above simultaneously

If you aren't running SLI or Crossfire, a good quality 500-650 would be plenty of power. A quality 600-650 should be able to handle any 2-card SLI or Crossfire, even with multiple hard drives. Excess is always better than inadequate power, but 1000W? No way your proposed system would need that.

For perspective: Look at my Systems 1 and 5 in my signature. Both are highly overclocked quads running modest video cards. Together those two systems plus a couple external hard drives and 20" LCD pull about 500 Watts. Oh, and that's with both computers' CPUs at full load. No, I'm not saying a 500Watt PSU could power both computers, but I am saying that above 750Watts PSUs are for bragging rights, blowing big chunks of money, or for seriously very high end multi-video card gaming rigs.

saltydog806

LOL Thanks. Just checking with the experts.

Leonardo wrote:

1000W PSU for a computer is essentially rediculous in my opinion, unless something like this:

4 X 8800GT
4 X HDD running in RAID
2 X optical DRIVE
dual monitors
CPU overclocked to the max running full load

....all of the above at once

If you aren't running SLI or Crossfire, a good quality 500-650 would be plenty of power. Excess is always better than inadequate power, but 1000W? No way your proposed system would need that.

Leonardo

Just don't misunderstand. The following principles are always true, not matter what PC generation you have:

PSU quality is worth the price
Excess power is better than inadequate power

But I stick to my comments about "rediculous"

HW_Hack

You need to very careful about just adding up all the current draw numbers and saying that will be the total power requirement .... at least for your standard PC.

For years that was how engineers approached the problem - but in doing actual power testing (at Intel as a designer) it was clear that we we're way over specing power needs. Yes every PCI slot needs so much current - video power - cpu power - memory - disks - etc.

But here is the crucial thing - the PC architecture itself (not even considering how the OS limits / controls activity) cannot have every device on (meaning in full use) AND - OR at max power at the same time ... just not possible. It really is a continual series "time sliced" power events across the the whole system.

So the actual Max Power number turns out to be somewhere between 50% to 70% of that sum of all current draw numbers. So for a lightly used system (basic usage) you can get by with the 50% number -- for a gaming or video production machine go with the 70% number.

Leonardo

But in most cases, quality trumps Watts total. I'm running a couple highly overclocked quad and dual core machines, full load, continuously with 2+ year old Antec 430s. In my opinion, most of the time, the monster output PSUs serve well for bragging purposes only.

scott

I am with Leo on this , a good high quality psu is the first concern.

But to be sure.... I butchered up a power cord so I could get an Amperage reading with my induction volt meter just to see how much my machine was really using.
Machine specs
Gigabyte PA-35-DQ6
Intel Q6600 3.2ghz 1.232vcore
2 gigs OCZ PC8500 Reaper
1 Optical drive
1 Hdd
1 swiftec water pump
1 120mm fan
3 80mm fans
1 EVGA 8800 GTS
OCZ 720 watt power supply ( 1 80mm fan )

So with the overclock , video card and waterpump I would say that it would be considered a heavy draw machine

I slipped my induction clamp over the black wire in the power cord and started the machine.
Peak reading during startup 3.0 amps ( 3 amps x 115 volts = 345 watts )
after it settled down to the desktop it hovered around 2.15 amps and full load folding 2.6 amps. So..
3.0 amps = 345 watts ( startup )
2.15 amps = 247 watts ( Idle )
2.6 amps = 294 watts ( Full load )

My APC battery BU software is reporting 292 watts ( Full load ) so That concures with my other readings.
My Feeling is that any "High Quality " 500-600 watt psu is plenty. Probably even for SLI.


Scott

Your-Amish-Daddy

So....Even doing my normal quad disk writing (I move alot of data during the day) Even I'd be under 400W?

scott

Your Amish Daddy wrote:

Even I'd be under 400W?

My guess would be yes. I just found a chart that says most HDD idle around 7-8 watts and under R-W conditions run about 12-13 watts But may draw up to 30 watts at start-up. But if you do not overclock or Fold , my guess would be your probably under 400 for most of day. Also note my numbers were for the "Box" only, no monitor.

Scott

edcentric

And remember that PSUs like to be loaded at 60-80% of rating. At real low loads the efficiency is poor.

bothered

I use a powered USB hub, rather than plugging it all in the PC, to help keep PSU load down a little. There can be quite a few USB devices.

Your-Amish-Daddy

I've got four USB devices, a card reader, my laser mouse, my compaq keyboard and my crappy Hauppage WinTVUSB

mmonnin

Leonardo wrote:

But in most cases, quality trumps Watts total. I'm running a couple highly overclocked quad and dual core machines, full load, continuously with 2+ year old Antec 430s. In my opinion, most of the time, the monster output PSUs serve well for bragging purposes only.

A 330W True Antec, originally bought for a 1800+ AGOIA, powered it, a 1700+ DLT3C, 2400+ M-Barton and all the way up to a 3200+ A64 +PCI-E video card with all systems having multiple HDDs and Fans. Voltage rails were always spot on even with the A64 system where it was probably loading the PSU down pretty good.

Quality is #1!