Desktop Power Supply problem

[tzones]

Hi,
I have two desktops at home one of them is an old Dell Optiplex GX 150(1GHz and 512MB Ram) and the other one is an assembled PC with (ASUS-A7N8X motherboad with AMD Athlon XP 2800+ i.e.1.8GHz processor).

Recently I've had power supply problem in the other pc with AMD processor which was originally a 300Watts I bought long back. Also I was not using the Dell PC that often as it is too old.

So I removed the power supply (which is 854JE Slim 110W) from the Dell PC and hooked it to the AMD desktop which is working perfectly fine even with a NVidia 8X-128MB AGP video cord. As a matter of fact the slot provided in the case for AMD is too big for the dell slim power supply to fit into but I managed it some how.

My question is whether it is ok to keep using it or does it goes cause power shortage problems which might affect the mother board in a long term? Can anyone please answer my question.

thanks in advance,
TZ

 

[RICHINMINN]

For an assembled system, a 300-watt power supply is less than I would ever consider using in it. (I normally use power supplies in the 400+ watt range.) A system with an Athlon XP 2800+, 512MB of RAM, an 80-GB 7200-rpm hard drive, a CDR/RW drive, a floppy drive, a NIC, and a video card with 128 MB of VRAM will require a constant flow of about 250 watts. I increase that by 50% for peak loads, which brings your power supply needs up to nearly 400 watts. If you ever plan to add anything else to your system (a second hard drive or optical drive, for example), allow a bit more.

The 110-watt power supply that you're using in your system now will not survive long!!! And when it dies, it may take major portions of your system with it! (little things like CPU, motherboard, hard drive...) I think you'll notice that the power supply gets very hot after the system has been running for a while.

Go out and get a new power supply of at least 400 watts, and do it quickly! Your PC is living on borrowed time.

RichinMinn

 

[Nelviticus]

There are quite a few on-line power supply calculators if you look for them:

http://www.google.co.uk/search?q=power+supply+calculator

I agree that 110W is far too low for your system and probably won't last long, but (no disrespect to RichMinn) I don't think you need to go as high as 400+W. Going that high won't hurt, and it will give you scope for expansion, but it will cost more unless you get a cheapo unit (which I wouldn't recommend).

You could ask ten different people about power supplies and get ten different answers (well, maybe six) - it's like asking "how big an engine should I go for when I buy a car?"

Regards

Nelviticus

 

[kmcferrin]

RICHINMINN, 300W was the official recommendation for systems that were using Athlon XP CPUs. This was back before we had power hungry video cards that consumed 100W on their own and required additional power connections. Things to think about:

1. The 110W rating on the Dell PSU seems kind of low. Are you positive that's the correct number?

2. Big OEMs (Dell, HP, etc) usually have more efficient PSUs than generic have. They are also usually engineered for a specific application, so you can rest assured that a puny 110W Dell PSU would be sufficient for the system that it shipped in, even if you added additional cards and drives.

3. You don't measure current in Watts, you measure it in AMPs. AMPs are generally more important when sizing a PSU, but it's hard to differentiate your PSU by it's ability to provide the exact specified current, but easy to do so with Wattage ratings.

I'd agree that the Dell PSU is probably not going to be up to the task of powering your current system for a prolonged period. Unfortunately, if your system draws more current than the PSU can provide reliably then you could end up blowing the Dell PSU and causing damage to your system board as well, so I would definitely get a new one ASAP.

As far as how "big" of a PSU you should get, that's more a matter of whether you plan to expand that system (or upgrade it later), or if you're just going to leave it as is. If you won't upgrade it, and 300W or 350W would do just fine, and will be cheaper. If you're likely to upgrade, I would probably go with a 500W or 550W unit just to give yourself some headroom.

 

[Aussie2]

tzones my first thoughts were some earlier Del pcs used proprietary power supplys not industry standard these being designed for Del motherboards only different wiring on the 20 pin connector

Good work getting your system up and running just the same... but it might be wise to shut down until you can purchase a new psu make it a good brand name and don't buy a cheap one

 

[Freestone]

One has to question just how much this old board can be upgraded to even consider a power supply greater than 300-350W. AGP is pretty much dead, Socket A is dead, so that leaves what? RAM and hard drives. Where is one going to use the excess power of 500+ watts? Maybe I am missig something.

Stick with a brand name power supply and avoid cheap, generic supplies.

And it appears the 110W is accurate. One of many Google hits on 854JE Slim:

http://cgi.ebay.com/NEW-DELL-OPTIPL...59029181QQihZ014QQcategoryZ3670QQcmdZViewItem

 

[burtsbees]

I have a 500W psu myself, and have hdd's RAID'd (RAID0, and the OS on a RAID1). I am not sure I am using close to that, but I don't think so. I have a total of 5 hdd's.

Burt

 

[RICHINMINN]

In response to kmcferrin:
The Dell Optiplex GX150 was originally configured with a 1-GHz Celeron or a 1.13-GHz Pentium III CPU, 256 MB of PC100 SDRAM, a 10-GB hard drive, a CD-ROM drive, a floppy drive, on-board video 4MB of shared memory, on-board audio, LPT port, 2 COM ports, 4 USB ports, and a 10/100 NIC. The Power Supply calculator at

http://www.extreme.outervision.com/psucalculator.jsp

gives a power supply requirement of 138 watts for this basic configuration. (The calculator doesn't include PIII processors, so I had to use the lowest-powered P4, at 1.3 GHz). Assume a bit less then, for the PIII. The video, being on-board, will require a bit less power than a separate video card. So the 110 watts of the power supply may be just on the verge of being big enough, assuming that the distribution of power (amperage) across the +12v, +5v, and +3.3v rails is optimized for their specific system.

And that's been my experience in working with big-name PC manufacturers like Dell, HP, and others: the power supplies they use are just marginal for the original configuration of the system, not allowing any margin at all for a more-powerful CPU, increased amounts of RAM, a larger (or second) hard drive, replacing the CD-ROM with a CD-R/RW, adding a DVD-ROM, adding components that are powered through the USB connection, etc. And the big-name manufacturers don't use a "more efficient PSU". Competition forces them to use the cheapest components available, and one of the first components to get replaced with a cheaper version was/is the Power Supply.

Replacing a power supply in a name-brand PC requires using a more powerful power supply, since we usually don't have the luxury of getting a power supply that provides power across the three voltage rails in the exact proportion as required by the system. You've got to make sure that the amperages on all three rails meet the requirements of the system, which means that you'll probably end up with more power than you really need on 1 or 2 of the rails.

Using a 110-watt power supply in a system like the Dell Optiplex GX150 is workable, but just barely. Using that same power supply in a system like the hand-built Athlon XP system, with a substantially more powerful CPU, more memory, a separate video card with a substantial amount of VRAM, a larger hard drive, and other unspecified components, is asking for trouble.

RichinMinn

 

[Aussie2]

Heres something to use up that extra power (agp not quite dead)

http://shopper.cnet.com/graphics-cards/xfx-geforce-7950-gt/4014-8902_9-32455174.html

 

[kmcferrin]

One has to question just how much this old board can be upgraded to even consider a power supply greater than 300-350W. AGP is pretty much dead, Socket A is dead, so that leaves what? RAM and hard drives. Where is one going to use the excess power of 500+ watts? Maybe I am missig something.

I'll agree that Socket A is (mostly) dead, but AGP is still alive and kicking. ATI is even released AGP versions of their latest video cards (at least up to the 2600 lines).

And that's been my experience in working with big-name PC manufacturers like Dell, HP, and others: the power supplies they use are just marginal for the original configuration of the system, not allowing any margin at all for a more-powerful CPU, increased amounts of RAM, a larger (or second) hard drive, replacing the CD-ROM with a CD-R/RW, adding a DVD-ROM, adding components that are powered through the USB connection, etc. And the big-name manufacturers don't use a "more efficient PSU". Competition forces them to use the cheapest components available, and one of the first components to get replaced with a cheaper version was/is the Power Supply.

That's exactly the opposite of my experiences. I've never had any issues with Dell or HP machines when adding more RAM, additional hard disks, RAID controller cards, video cards, CDRW drives, or multiple USB devices. Granted, I typically only deal with their business lines rather than consumer models, but it all works fine for me.

As regards the "more efficient" comment, perhaps that was phrased poorly. I meant to convey that the PSUs aren't generic off the shelf models, they are usually designed for a specific model PC. Because of that they are able to tailor them to that's PC's characteristics and expansion capabilities (i.e., provide the correct amount of current) without having to resort to "big wattage numbers" that has become commonplace in the third-party PSU market. So while I didn't mean to say that the PSU was more efficient than generally available models (in the power loss during conversion sense), I did mean to say that they are designed to make more efficient use of the power subsystem.