Athlon Power Draw?

Arjay13 · February 13th, 2002, 04:34 PM

Anyone know the current/power draw of an Athlon? I ask because in a different forum, it was stated that the wattage of a power supply was not the important spec as far as running an Athlon. They said that the PS's ability to maintain the 5volt rail was the important spec.
This made me think about the power draw of the CPU. From the AMD site,the Athlons nominally draw 35Amps at 5 volts or 175watts. This is 60-70% of the wattage of most PS's and I can see how it could impair the ability of the PS to maintain 5 volts. Did I do this calc correctly?
Any thoughts on this? Thanks in advance.

FreakyOCR · February 13th, 2002, 04:37 PM

This is what I know... 300watt recommended

Athlon is suposed to take 55w... but I may be wrong...

Enermax PSU are not recommended for Athlons because of a flaky 5v rail that Athlons have a hard time dealing with..

I highly doubt the draw is 175w... but for all I know it could be...

Arjay13 · February 13th, 2002, 04:45 PM

I wasn't certain what voltage to use. The current data was associated with the Vcore voltage of 1.75. For 35 Amps that makes 60 watts which is in line with your data. But it seemed in the AMD spec sheet that the currect came in on ther 5 volt line which would result in my higher wattage.

Regardless, 30 - 40 Amps is a considerable load on the power supply!

FreakyOCR · February 13th, 2002, 05:45 PM

Yeah... I don't know what kind of amps the CPU draws... but maybe AMD misreported it... who knows...

DanU · February 13th, 2002, 06:02 PM

Here is a very useful link that lists the specs for most x86 processors:

http://users.erols.com/chare/elec.htm

Multiply the current by Vcore, not 5V, to get the power consumption of the core logic.

lost · February 13th, 2002, 06:55 PM

A XP 2000+ under max load 40 amps with a core voltage of 1.75 nominal which give use 70watts max. Typical amps for this CPU is 35.7 amps at 1.75 with 62.475 watts. The five volt rail is used to get the core voltage, the motherboard has a voltage regulator on it. The more load put on the a power supply the more problems it has mantaining a steady output. There are a few other factors involved but enough is enough.

Arjay13 · February 14th, 2002, 09:59 AM

Thanks for the info Guys!

ChoaticWhisper · February 14th, 2002, 10:07 AM

I found this the otherday. I dont know how true it is so....

Quote:

Power supply: How big a PSU do I need?
list complied by RudyG from ttzforums
AGP video card - 20-30W
PCI video card - 20W
AMD Athlon 900MHz-1.1GHz - 50W
AMD Athlon 1.2MHz-1.4GHz - 55-65W
Intel Pentium III 800MHz-1.26GHz - 30W
Intel Pentium 4 1.4GHz-1.7GHz - 65W
Intel Pentium 4 1.8GHz-2.0GHz - 75W
Intel Celeron 700MHz-900MHz - 25W
Intel Celeron 1.0GHz-1.1GHz - 35W
ATX Motherboard - 30W-40W
128MB RAM - 10W
256MB RAM - 20W
12X or higher IDE CD-RW Drive - 25W
32X or higher IDE CD-ROM Drive - 20W
10x or higher IDE DVD-ROM Drive - 20W
SCSI CD-RW Drive - 17W
SCSI CD-ROM Drive - 12W
5400RPM IDE Hard Drive - 10W
7200RPM IDE Hard Drive - 13W
7200RPM SCSI Hard Drive - 24W
10000RPM SCSI Hard Drive - 30W
Floppy Drive - 5W
Network Card - 4W
Modem - 5W
Sound Card - 5W
SCSI Controller Card - 20W
Firewire/USB Controller Card - 10W
Case Fan - 3W
CPU Fan - 3W

Arjay13 · February 14th, 2002, 10:20 AM

So, given some sort of nominal configuration, you can expect to use about 170 - 200 watts of power or about 60-80% of its rated capacity. What attribute of a power supply enables it to maintain its voltages within specs while under load? Or do we just buy the largest wattage PS we can afford and assume that it will be sufficient?

swamp-fox · February 14th, 2002, 10:20 AM

hum I'm no electrical engineer but I don't think the whole computer and monitor would pull more than 1/2 amp if that. I know most houses have 15 or twenty amp breakers for a circuit, and that could have fridge, microwave, lights etc on one circuit. Is that miliamps or something or am I just confused????I can't remember the formula.watts X volts = amps?? Where's a good elec engineer when you need one.

swampy