How much will a 300w power supply run?

PSUs: The source of DC power for all components in the PC & often a big noise source.

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How much will a 300w power supply run?

Post by GamingGod » Wed Jan 29, 2003 10:35 am

Anyone with a 300w power supply that is pushing alot of juice, multiple hard drives, ect. Post your system specs and maybe we can get rid of these rumors that you need a 400w+ power supply to run a high performance rig.

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Post by Bluefront » Wed Jan 29, 2003 4:46 pm

Well I've got an Antec SmartPower 300w. No problems.

Gigabyte 667Ultra.
Samsung 512DDR
Celeron 2.0
2 80mm case fans
4 60mm hard drive fans
1 60mm cpu fan
1 40mm chipset fan
2 Maxtor 7200 hard drives
1 Samsung cdr/dvd drive
1 Panasonic dvd-r/ram drive
1 internal multi-card reader
1 firewire pci card
1 scsi pci card
1 pci modem
1 DigitalDoc5
1 floppy drive
1 slot fan
1 ATI AIW 7500
Intel Wireless ps2 keyboard/mouse reciever

No wonder the thing's so damn heavy....No hint of any power related problems.

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Post by MikeC » Thu Jan 30, 2003 1:24 am

Seasonic SS-300FS APFC PSU modded w/Panaflo L (super quiet as default voltage to fan is ~4.3V). Perfectly stable with...

- P4-1.8A oc'd to 2~2.4G or P4-2.8GHz
- 512 mb PC266 DDR RAM
- 3 Panaflo fans
- Matrox G400 Max VGA or GF4800/128 mb
- Gigabyte GA-81RXP board
- CD ROM (40x) generic
- LG 48x24x48x CR-RW
- scsi card for scanner
- 2 Barracuda IV drives (20 & 40G) -- occasional 3rd drive in mobile rack for backups.
- floppy
Last edited by MikeC on Sun Aug 17, 2003 9:06 am, edited 1 time in total.

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Post by powergyoza » Thu Jan 30, 2003 1:24 pm

My geek pursuits have taken me far off into the deep-end, but your benefit. I'll be getting a clamp-on DC ammeter soon, so I can measure DC current draw from the IDE connectors. Then we can figure out our true PSU requirements!

Stay tuned!

Mike, we could incorporate this device into future reviews/article. What do you think?
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Post by MikeC » Thu Jan 30, 2003 1:57 pm

powergyoza wrote:My geek pursuits have taken me far off into the deep-end, but your benefit. I'll be getting a clamp-on DC ammeter soon, so I can measure DC current draw from the IDE connectors. Then we can figure out our true PSU requirements!

Stay tuned!

Mike, we could incorporate this device into future reviews/article. What do you think?
Sounds fun. Play with it & see how well it correlates to other data, then sure, why not?

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Post by jamoore9 » Thu Jan 30, 2003 2:06 pm

Make sure you get a good PSU. A well made PSU will push well-over its rated power, as I'm sure is the case with the Antec TruePower 300 above (sheesh!).

Check out Tom's Hardware's PSU round-up: they measure the "breaking point" of PSU's (where they will auto-power-down) as compared to their rated max power. The best performer in their estimation, a Verax 300W, actually pushed 370W.

After reading that, I did some digging about the best rated PSUs according to Tom's (Verax, Conrad, Herolchi) and and found out that Verax PSU's are made by Fortron, as are Conrad, which also markets as Sparkle here in the states. They also make AOpen's PSUs. So a Sparkle FSP300 is the same product as a Verax FSP300 (which Tom's reviewed), is the same as a Conrad FSP300. Similarly, what Tom's calls "Herolchi" is actually Heroichi, and is marketed in the states as Compucase (as is any other PSU maker that uses HEC in their PSUs). I'm running an HEC-350LDT -- oh, that's important! Only get an HEC with a "T" at the end. It's for "turbo," and means that it is ATX12V compliant (P4 ready).
Last edited by jamoore9 on Tue Feb 04, 2003 2:03 pm, edited 1 time in total.
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Post by Herb W. » Thu Jan 30, 2003 8:21 pm

Anyone buying a PSU for a gaming rig who has an eye on future upgrades needs to keep in mind that the recent history of graphics card upgrades suggest that you be generous in providing a power cushion - a 9700 Pro has a minimum requirement of a 300 watt PSU, and depending on what source you go by, the Geforce FX needs a minimum of 300 or 350 watts. Throw in a 360 gig RAID array, 1 gig ram, 3 gigahertz P4, and a few other drives, and while a 300 watt PSU may run your box, you can probably forget about stable overclocking, and you'll probably need to buy a new PSU for your next upgrade. Some cheaper 300 watt supplies don't provide enough juice on the +12 rail to safely run a current state-of-the-art P4 system - see Tom's review. And a year or two from now gaming GPUs will probably be guzzling 120+ watts...

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Post by schnee » Sun Feb 09, 2003 11:49 pm

On my 300w Zalman PS:

768Mb DDR 2100
Radeon 9000 Pro (w/ Zalman passive HS)
320Gb of storage
- 2 x Western Digital 100Gb SE (RAID 1, in SmartDrive enclosures)
- 1 x Western Digital 80Gb (in IDE pullout cartridge, not always in)
- 1 x Barracuda IV 40Gb
2 PCI cards (USB2/Firewire, Hercules Fortissimo - negligible draw)
5 fans (80mm PapstNGL - negligible draw)
2 powered USB devices (tablet, scanner - negligible draw)

I don't overclock, but I do run some pretty demanding stuff - Photoshopping and FPS gaming - and it's rock-solid stable.

Yes, most 'enthusiasts' overbuy. :)

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Post by Herb W. » Mon Feb 10, 2003 1:20 am

Re Schnee's system - valuable information there. It should be kept in mind that a current high-end 3d card like a 9700Pro or a Geforce FX is drawing 30+ or so more watts than a 9000; and if you were to array a pair of the new Barracuda 7200.7's rather than the WDs, you would be looking at an extra 19.2 watts max draw on the drives. Plus any significant overclocking can add significantly to your load - all those extra watts being dissipated as heat.

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Post by GamingGod » Tue Feb 11, 2003 8:03 am

Yea but you would still be talking about 200w at most.

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Post by Herb W. » Tue Feb 11, 2003 8:29 pm

Maybe 200w on average use, but not on momentary max draw - see the Tom's Hardware website for the calculations on components.... Granted, you may never hit such extremes as 90-100% on all components simultaneously, but if you want to be certain of avoiding any instabilities caused by voltage drops, you are better off playing it safe. Check the VIA forums for many cases of problems caused by weak 250- and 300-watt PSUs - there are endless litanies about lockups/looping that turn out to be caused by low and fluctuating voltage, especially for the overclocker. And there is also the issue of what each rail delivers relative to your component loads - looking at the total number of watts can create a misleading impression that "everything's fine".

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Post by powergyoza » Fri Feb 14, 2003 3:59 pm

I just posted a new topic in this forum about my dualie's power consumption. Check it:

In short, at the very least I need a PSU that can supply 30A on the 5V line - ie 300 watt PSU and up. If I upgraded my video card to something hotter, I might need something larger.
FS: SX1040, PSU duct, TigerMP, 2x1.4GHz, 'Cuda7 120GB, dcupld L1As (6V) ([url=]link[/url])

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Post by arif » Wed Feb 19, 2003 11:55 pm

Here we go:

After being inspired by so many working with so little power, here's my new setup:

Nexus 3000
Athlon 2700+
A7N8X Deluxe (w/ dual onboard LAN, nforce audio, firewire, usb x6, etc)
MSI GF Ti 4400
2 HD:
180GB IBM 180GXP (solid drive and quiet)
30GB Maxtor DM40+ (noisy, evil drive that's being removed tonight)
SLK-800 + Panaflo L
2 case Panaflo L

System works great! As I stress it even more over the next few days, I'll put that PS to task, but I'm sure it will perform. The Nexus 3000 seems to be going very far - highly recommended.

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Post by Herb W. » Sat Feb 22, 2003 9:20 am

digitalix wrote:might as well hop on the bandwagon:

...i haven't had any problems yet, it's dead silent as well, can i ask for more? i'd say 400w would only be needed for high end raid setups or dual processors...
Looking at your setup (which is very close to what I am planning), and working from Tomshardware figures and the AMD "100% CPU load plus 80% of all other loads" rule, you're actually past the 15A max load the Nexus is rated for on the +12v rail... better not try any overclocking!

Unfortunately, an "upgrade" to most quiet 400 watt PSUs won't help - most of these units (including the SilenX) put all the extra power on the 3.3 and 5 volt rails for some reason, leaving the 12 volt rail at 15A :( . The only ones I have found that seem to buck this trend are the 400/460w "Ultra-quiet" PSUs from

I'm not arguing with the general consensus here that in most cases, virtually all of the time even heavily loaded systems will run well on a good 300 watt PSU. But from problems reported on other forums, PSUs that even momentarily get close to their limits are much more likely to experience voltage drops on their rails, which can cause instabilities (lockups, looping, etc.), especially for overclockers. That 30 millisecond spike in demand every 8 hours, if it causes your system to crash, is the one spike you want to be prepared for. To give but one example from forums, some Intel 845PE chipset motherboard owners have reported problems cold booting with nominally "OK" PSUs because the momentary draw on drive spinup etc. is just too much for the PSU to reliably support at the right voltages. I for one intend to err on the side of caution in PSU choice, as I will be doing some mild overclocking...

A related point for overclockers to consider is that some of these very quiet 1-fan PSUs push so little air that case temps (already raised by o'clocking) could rise enough that thermostatically-controlled CPU heatsink fans are triggered to run faster and louder, or a need could arise for more case fans, thereby obviating the noise reduction benefit of the PSU.

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Post by Vernacular » Thu Mar 20, 2003 8:10 pm

40 Gig hard drive
12 Gig hard drive
Samung CDR/CDRW/CD drive
Creative CDR/CDRW/CD drive
Floppy drive
250 Zip drive
Soundblaster Live! X-Gamer sound card
2 x GeForce 3 Pro video cards (dual monitor setup)
Athlon Thunderbird 1.1 Ghz processor
ABIT mobo
300w Sparkle PSU (soon to be replaced by a Nexus NX-3000)

I thought I had a nice setup, till I saw some of what you guys are running. Sheesh. :D

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Post by Tigr » Fri Mar 21, 2003 1:39 am

Compaq Proliant with a 250 Watt PSU:
550 MHz PIII
~300 MB RAM
1x Maxtor 4 GB
2x Seagate Barracuda 80 GB
1x S3 video
2x Ethernet (3COM + Intel)
1x ISA SoundBlaster

The PSU weight is about the same as a contemporary Enermax for 350 Watt.

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Post by Radioactive » Sun Mar 30, 2003 1:10 am

Fortron P30060ATV 300 watt (panaflo L1 modded)
XP2100 thoroughbred-b oced 2255 mhz 1.85V (panaflo L1 over cpu)
epox 8rda+
3 sticks of ram
6 switch baybus x 2
3 panaflo L1 rear+back
plextor 12/10/21A
wd 80 gig
geforce ti 500 oced 265/580
usb hub x 2
notebook usb led light
ati tv wonder pci card

Stable for the past week+ running 24/7 playing c&c generals or prime 95 most of that time.
I will add another 120 gig hd, cdrom, and a front 120 mm fan soon.
3,5,12 V fairly stable according to mbm. The main reason to go to a 400 watt is the larger heatsink on the mosfets as show in the other threads. There seem to be more components inside too on the 400 watts. Your sysem might never need the extra juice, but the psu will run cooler, extending its life.

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Post by mrporkypig » Sun Apr 13, 2003 11:19 am

Fortron P30060ATV (running at 5V)
P4 1.7 OC'ed to 1.95
Asus Geforce 3
Asus P4T
512mb Rambus
3 case fans
Maxtor 80GB
Asus 52/24/52
LG 16/10/40
Sound Blaster Live

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Post by Rod M » Sat Apr 19, 2003 7:19 am

Antec truepower 330 watt

MSI k7d master dual AMD board
2x AMD MP1200 @1350mhz
6x 80mm fans
1x 40gig HDD
1x DVD drive
1x scsi CDrom
2x 64bit 10/100/1000 network cards
1x GF2 MX
1x creative vibra 128
1x adaptec scsi card

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AOpen 300W PSU

Post by dago » Tue Apr 29, 2003 8:23 am

very old 300W PSU Aopen, has run a long way since I bought it in '99 (IIRC) and very quiet also ...

now running :
- Soltek MB
- Duron 750
- 3 NIC : 2 ethernet + 1 pcmcia+wlan
- 1 Adaptec UW
- 5 HDD (3 IBM, 2 Fujitsu)
- 1 Plextor CDROM
- 1 Creative 3dfx Banshee video card
- 1 FDD
- 1 120mm FAN
- other things that I forgot in there (highly possible)

and all of that is very quiet ... once I close the closet door
UPDATE : even more quieter since moved to lab room @work
Last edited by dago on Tue May 20, 2003 11:15 am, edited 2 times in total.

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Post by edcrane » Fri May 09, 2003 11:23 am

-antec 300w psu-

p4 2.53
3x 512mb pc3200
dvd rom
4x 7200rpm HDs (160gb,120gb,80gb,40gb maxtors + WDs)
2x Papst 80mm 12db's
1x 80mm Directron Silencer @ 5v
Ti4600 w/cheapo thermaltake fan+fanmate (i need a zalman)
3 PCI cards including addtnl' NIC, IDE controller, addtnl' 5.1 snd.

This is on an albatron 845PEV

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Post by digerati » Sun May 11, 2003 12:31 am

Antec PP303XP 300w PS

AthlonXP 2100+ tbred
Epox 8rda+
2x256 spectek pc2700 ddram
ATI Radeon 9500 Pro
Western Digital Special Edition 80gb
liteon 24x cdrw
toshiba 4x dvdrom
sony 52x cdrom
Soundblaster live! value pci
ATI tvwonderVE pci
Sony 3.5 FD
3 80mm zalman case fans
Vantec Aeroflow

Been running stable for almost 2 months now

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Post by AndrewC » Sun May 11, 2003 7:01 am

Antec SmartPower 300 watt

AthlonXP2100 Palimino
256MB PC2700
MSI KT3 Ultra2
60GB Maxtor Plus9
Samsung CDRW
Pioneer DVD
2 Case fans at 5v
PNY G4Ti42008x

No Problems

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Post by Athlon Powers » Tue May 20, 2003 9:02 am

Antec TruePower 330w

Athlon XP 1700 Palomino
MSI KT3 Ultra
512MB Kingston PC2700 DDR
ATI Radeon 9000 64MB (passive cooling)
Linksys LNE100TX NIC
Hercules Fortissimo III 7.1
Maxtor DiamondMax 8 40GB 7200RPM
Western Digital 10GB 4200RPM
LG 8160B 16x10x40CDRW

3 Chieftec Case fans at 5v (almost no airflow, need new ones...)
1 Panaflo L1A on AX-7 heatsink

Nothing real taxing but it's stable, almost quiet and it works so Im happy.
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250W is not enough

Post by Growler » Wed Jun 04, 2003 6:39 pm

I have had problems with my 250W Q-Technology ATX1125B power supply not able to support my newly upgraded system. Symptoms are program crashes, system lockups, and system won't post (stops before executing memory testing). I have unplugged my SCSI Plextor PX-32TSI UltraPlex and underclocked my system to avoid these problems for now.

The PSU was installed in 1999, perhaps age has derated its capacity somewhat. Nevertheless, since 250W is borderline I don't want to upgrade to a 300W. I would like to continue upgrading my system including increasing the speed again and getting a DVD. I have no confidence 300W would be enough, and only wish to upgrade the PSU once.

Athlon XP Barton at 1.0942 Ghz (FSB 99.5 Mhz, multiplier X11)
512MB ram stick @ 198.9 Mhz
ASUS A7N8X Deluxe ver2.0
PNY GeForce FX 5200
Quantum Fireball SE 4.3 Gb 5400 RPM
Quantum Fireball 30Gb 5400 RPM
SCSI card
Plextor SCSI PX-32TSI UltraPlex
USB card

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Dual redundant power supplies?

Post by scalar » Thu Jun 05, 2003 12:14 am

It'll be interesting to see how long it takes until pairs or triads of power supplies start becoming common in home computers.

I have an old Dell PowerEdge 6300 server with three power supplies (accepts 4 Pentium II 450 Xeons, up to 8 Ultra160 hotswap 15,000 RPM hard drives, etc etc). It requires two of the power supplies to run, but will distribute the power evenly across three, and tolerates a sudden power failure (or circuit failure) on any one of the three supplies.

I can see power supply pairs or triads happening in home computers once people are buying 800 watt power supplies for their home computer/furnace.. :)


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Post by Susquehannock » Thu Jun 05, 2003 9:49 pm

PSU = Fortron FSP300-60ATV

This is one very impressive 300w PSU. It was able to power the
whole array you see below with little heat. :shock:

regular everyday components:

Mobo: ABIT - KG7-RAID v1.0

CPU: 1700+ JIUHB dLt3c at stock settings

HDDs: Two 7200rpm 40Gb IBM in RAID 0

Graph. Card: Radeon 9500np (haven't tried 9700pro hack yet)

Sound card: T.B. Santa Cruz

NIC: D-Link DFE-530TX Ethernet

CD/RW: PlexWriter 48x24x48

DVD: Sony

RAM: TwinMOS pc3200 (bh-5 Winbond)

HSF: Thermalright SK-7 - 80x25mm generic blue UV reactive fan

Case fan: 80x25mm generic blue UV reactive fan

PCI slot vent: Two 45x15mm fans

Keyboard: Black USB Dell Internet w/Quiet keys

Flash card reader: Sandisk ImageMate

Lighting: Two 12" UV ColdCathode & Two sound reactive blue LED units

extra components IN ADDITION to above.
These were connected through ONE molex for testing purposes in an
attempt to trip the overload protection

Two 80x25mm generic blue UV reactive fan,
One 120x38mm Sunon Tornado & One 120x25mm Enermax adj.
Two 40x28mm Sanyo Denki Super Tornado fan,
One 12v clamp light,

Amazingly, I ran out of 12v components to plug in before the
overload tripped.
All the above and the unit still asked for more! :D
It was hardly even warm!


All in all ... this PSU is the best $27 I've ever spent.:mrgreen:
Last edited by Susquehannock on Thu Jun 05, 2003 10:00 pm, edited 1 time in total.

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Re: AOpen 300W PSU

Post by Susquehannock » Thu Jun 05, 2003 9:53 pm

mrporkypig wrote:Fortron P30060ATV (running at 5V)

If I may ... what is meant by "running at 5v"?

Have you modded the PSU to supply all it's power to only
one rail? I have heard of people doing that before.

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