I'm real happy with my old pc that is now an mp3 server with Slack 10.1, gnump3d, and no-ip.com. My pc is an old 200 MHz Pentium pc with a PCI IDE controller card, 2 80 GB IDE harddrives, 64 MB RAM, ISA soundcard, PCI network card, cdrom burner, and DVD player. There is no CPU fan on this old mobo, just the power supply exhaust fan and an air opening in the front of the pc that creates a "wind tunnel" from the front of the pc to the back. The pc runs 24/7 connected to DSL.

That's my setup and my pc exhaust air feels cool. I'm thinking about replacing the power supply since it's 3 years old...it's 350 W. How much power on a new supply do I need (350 W)?

EDIT: My concern is that if I get a lot of people on my server at once that this old CPU would not have enough power to serve. Should I be concerned about that? How much power would this pc need if 50 people were logged on at the same time?

I would replace with at least what it has.... If you go higher wattage, the ps should run cooler (Like a V8 in a Vega), but don't go lower (Like a 4cyl in a 18 wheeler

My fileserver at work (serving 50+ employees) used to run a 1.1G, 256MB ram setup. It was ok, but long directory listings took a few seconds. I recently upgraded to a 3200+ AMD64, 1.5G ram with just a moderate speedup in services.

What was your power supply on the old server?

You really need less wattage than you'd think. I'd say the old setup's PS was no more than a 250W.
Check this calculator out: http://www.adecy.com/psu/

Hi,

Your concern for the PSU is valid. The supply you have for that class of machine was most likely a 230W or 250W originally. Since the current PSU is 350W, I would not replace it with anything smaller.

Your load for the MB is not going to vary much. Your concern should be for the peripheral devices, hard disk, cdrom or cdrw. That is were your margin load will be.

Now for the user load question. Your system will load relative to activity of the users' on the LAN. The PSU will vary but the change is minimal. Your service load will definitely vary and be dictated by the CPU load by the OS service. This limit will cause more peripheral activity thus the PSU load will increase or decrease relative to this activity. This is were you need to make sure that the PSU is adequately sized to meet the load.

I've got a small server with a k2-90 and it just services the LAN needs. I use my routers mixed with switches to create my firewall needs and leave the server for services. The server is in a mini-at tower with just a 250W PSU, 2 6GB ata drives and a cdrom.

I am going change the MB with a k6-450. The PSU will remain the same.

This is a nice calculator. It came up with a 53 W power supply for a P4 CPU @ 1.2 GHz (lowest speed intel but overkill in my case of a Pentium I @ 200 MHz). My 350 W supply is way sufficient, but I won't downgrade either.

Thanks for all the help!

If you are afraid of such thing, you better buy a fan for your cpu, because the power of your psu is more than enough. High wattage is needed if you have a modern agp card and spend much time playing 3d games. However, it's not your case.

ok-I'll look into a case fan or cpu fan/heat sink. My power supply seems to be delivering enough power and keeping everything cool (it's a dual fan antec that's 3 years old). Is a new power supply recommended yet since all seems good?

If everything works well, why to change?

I opened up my pc and realized that there is a heat sink on the cpu. I have a case fan that would mount nicely on the inside bottom of my case. Unfortunately, the 2 prong plug on the fan doesn't fit the 3 prong CPU fan slot on my mobo-could there be a slot marked CASE FAN on my mobo? A PDF drawing of my mobo would help-I took the #s off the mobo:

ISLT72209792

AA
678409-102

It's an old Intel Pentium ATX board from 1997. I googled around and found nothing.

Hi,

You could always take power from a molex power plug for the 12VDC for the fan. You can get mating plugs for the fan.

The only thing you have to be very wary is is that Pentium I systems weren't ATX (nor were early PII systems) and so used a different connector (or pair really) from the Power Supply, had less pins and no ACPI support.

Hi,

Maybe I should be clear! Take power from the peripheral molex plug (four pin) for the the fan by using the before mentioned adapter. I would not take power from the motherboard molex, be AT or ATX configuration.

The peripheral molex is the same for AT/ATX. As for the 3 pin connector on the MB, I only use the CPU fan then all others use adapters with the peripheral service molex connectors. Most of my systems have at least 4 fans. Front, side over the CPU, exit back and of course the PSU. The boxen have a balanced air flow.

My post was in reply to the OP, either I misread what he wanted or he's edited since. Thing is, if you buy an ATX PSU for an old AT Motherboard, you will not be able to power the motherboard, only the peripherals as the connector for the power to the motherboard was different back then