[RESOLVED] Power supplies and PIII
Results 1 to 11 of 11

Thread: [RESOLVED] Power supplies and PIII

  1. #1

    Question Power supplies and PIII

    Most of my recent work has been with AMD processors. I'm aware that 300+ watt power supplies are said to be "absolutely necessary." However, I've been a reluctant Tech, and not willing to buy into that advice without some real exploration of my own. I've stuck with the standard 250 watt PS that comes standard in the medium priced cases I employ in new builds, and I had had surprizingly reliable results. I have learned that improving case ventalation seems to have more to do with this reliabilty than watts, and now that I've explained that I am aware of PS issues, here's my question.

    Due to prices and availability, I'm tempted to experiment with the P3, 1 gig and up family, and I am concerned about PS requirements and performance. Are there any minimums to be met? Is ambient case temps as critical with P3 as they are with AMD? I am looking at a line of mobo/chip combos that are inviting as upgrade kits for the line of Celeron 300s I sold a few years back, and I'm wondering if I should factor in a new PS/Case with the offer. Any and all advice is welcome, I've been an AMD fan to long now, and need to catch up.

    Thanks, be safe.

  2. #2
    Registered User
    Join Date
    Oct 1999
    Clackamas, OR USA


    PIII's don't have the same heat problems....With the Intel builds I just use a standard case with a generic 250 or 300 WATT PS depending on how many drives etc. the system will have or whether it's likely to be upgraded in the future, a heat-sink and fan that wholesales for $5.90, and no extra fans in the case. I had a lot of problems attributed to defective PS's last winter but after changing vendors that problem was handled....

    Note to self: Re-index brain cells, database corruption present.
    "Badges? We don't need no stinking badges."

  3. #3


    well, put it this way - I'm running the following...

    Supermicro p3tdde (onboard: IDE raid, LAN, 3 USB)
    1 - p3 1.26ghz at 512k
    3 UDMA 100 HDs - 2 at 5400, 1 at 7200
    3 CD drives (48x, cd-rw and a 16x dvd)
    896 megs of pc 133 ram
    5 case fans (just cause I can)
    Geforce 2 64meg
    Sb live
    TV tuner

    ALL off a 300w p/s I bought a few years ago

    Just because is shouldn't work, dont mean it won't.

  4. #4


    Usually a 250 watt p.s. is all that is needed for a PIII, PII, or Cel. If there are going to be alot of hd's, cd-roms, geforce cards and so on inside a tower case, then maybe a 300 watt.
    P IV's will need a special power supply because they use 3 different power connectors on a pIV mainboard that uses RAMBUS ram. Suggest min 300 watts.

    If Hannibal were a pc support tech,
    He would invite the stupid user over for supper.
    "Tonight, I shall feast on stupid user's brain" ffffttffftftftfftft

  5. #5


    It's possible but not recommended to run a p3 with 200 watts, that is what Dell ships P3s with. But I'd recommend at least 300 watts for any system.

    I am JungleMan.

  6. #6


    The requirement for high output power supplies is totally overblown IMHO. The big PC makers like Dell and HP ship with some really weird PS's - 170W for example. And they last for years, too.

    Unless you are running an 8 disk RAID array, you don't need a 300W PS.

    I help others in the name of my Lord, Jesus Christ.

  7. #7


    PIII's run fine on 250watt power supplies. I had one that ran for a couple of years that had a Voodoo 5, two hard drives, the floppy, the mobo, and two CD drives. I'd go with at least a 300watt now just because of case fans. Some of the 400/450watt power supplies have a nice intake and exhaust to take out the hot air.

  8. #8


    i rememeber when i was running a p2 350 (AT BXCEL board) on a 150watt power supply with 2 hdds, cdrom, writer, and other things plus slaving the monitor off the back,.. dang was i lucky

    but now i just use what comes in the box, its alot easier

    If You Cant Beat It, Bin It....

    Just A Thought

  9. #9

    Thumbs up

    Thanks to all for your advice. I was never sold on the 300 watt PS requirement, other than how the exhaust fan addressed case temps. I'm building mild mannered boxes, Chevy sedans not Winston Cup/NASCAR racers. If the customer junks it up after the fact, maybe a PS upgrade is a thought, but I too have noticed the low powered PS from the big boys. Thanks again, y'all be safe.

  10. #10


    I sell nothing lower that a 300w Power Man power supply unit. We sell InWin cases and thats what they put into the case for P3's, P4's and AMD's. Even on older P2 Pc's I found that most people have added memory, Nic, Usd Devices, 2nd Hdd's, Dual CDrom (CDRW, DVD). I figure the better the PS the less chance the customer's going to come back complaining.

    "The labor's free, it's your attitude that costs $45.00 an hour."

  11. #11
    Darren Wilson


    P3's will run quite nicely on a 145W M-ATX PSU & Case if you are using 1 HDD, CDRW, CD/DVD-ROM, with no problems. Used to sell a few M-ATX setups to businesses with the above in and never had any problems.

    FINALLY, Rocco HAS COME BACK to Win-Driverssssss......
    Let the Boobies hit the floor


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts