Have to choose between 2 PSU, need advise

[rui]

Hi:

I have a AMD Athlon XP 1600+ (1,4 Ghz), which is OC to 1,55 Ghz (10,5*148). I am using a MSI K7T Turbo2 (VIA KT133A chipset).

Recently my PSU went to a better world ;), and i have the option of choosing between two used ones that a friend of mine can spare. Both are 300 W psu’s.
I’ve tried both, and they seem stable with my overclock.

But they report different outputs, when using the latest motherboard monitor:

+3,3 V line: the first one goes to 3,29 ; the other goes to 3.31

+5 V line: the first one goes to 5,13 ; the other goes to 4,96

+12 V line: both go to 11,87~11,90, none of the two reaches the 12V.

I am asking for advice, because i’ve read somewhere in the net, that tha AMD’s feed themselfs from the 5V line. Is this true? If yes, then my choice is clear (the first power supply).

Thanks to all in advance.

[da franksta]

dear rui,

so we meet again.
it's true the +5V line is rather important for the proper functioning of AMD processors. however, it's not the voltage that's important, it's the amperage. a good PSU has 30A (max) or more at the +5V line. you should look into this before making a choice.

cheers :)

[rui]

Originally posted by da franksta
dear rui,

so we meet again.


Lol. Hi da franksta. :)

Originally posted by da franksta


it's true the +5V line is rather important for the proper functioning of AMD processors. however, it's not the voltage that's important, it's the amperage. a good PSU has 30A (max) or more at the +5V line. you should look into this before making a choice.

cheers :)

Humm.. i will look into it.

Thanks

[Scuba]

After having two PSU's exploding on me in the last year I can say only one thing.
Select the PSU that say Enermax 550W

300W is too small, and next time you might loose more parts as well.

[rui]

Well, my problem is that here in Portugal it's very difficult to find brand PSU's :(
As of today, I couldn't find any Enermax, or Antec, or any other recognized brand.

Now, the PSU’s I have available are: Chieftec HPC-300-202, and Macron Power MPT-300

The first one has this output values:

+3,3 V: 20 A
+5 V: 25 A
+12 V: 13 A

The +3,3V and +5V have a joint power output of 165W.

The second one has this output values:

+3,3 V: 14 A
+5 V: 30 A
+12 V: 10 A

The +3,3V and +5V have a joint power output of 160W.

Now, I was under the understanding that the important for the Athlon’s is the +5 V power line. But I found out that the +3,3 V line is also important. Is this correct?

What advice can you guys give me?

[theReal]

It depends on the board you have - one board I know that ONLY uses the 5V line for both 3.3V and 5V is the Epox 8K7A. For this board, a perfect PSU is crucial, I don't know about yours.

If I were you I'd go to the forums on www.amdmb.com and look for people who have the same board and ask them for advice.

btw. Enermax is NOT the first choice for boards that only use the 5V line - IMO Enermax is not as good as people think. Their 5V lines are often unstable and the fan design is a complete construction error (the 9cm fan at the bottom is stronger than the 8cm fan which is sucking the air outside - that results in a lot of hot air from above the cpu being blown INTO the case again...)

I have a Leadman Powmax 400W PSU - all voltages are near perfect on an oc'ed Epox 8K7A+, T-Bird 1400, Rage 7500 graphics. Before the Leadman I had an Enermax 350W which made my system useless, even not oc'ed the 3.3V went down to 2.8V when I put load on CPU and graphics adapter, the 5V was at 4.7V even when idle. As you can guess it was very very unstable...

[chemmajik]

The key feature to look for is the 3.3v & 5volt lines adjustable internally, if you are going to spend the bucks get the adjustable one!

[VorteX]

I would recommend the fist one because of the high amps in the 3.3v and 5V line and if you are considering of getting a enermax PSU i would recommend you have a look at this thread http://forums.pcpowerzone.co.uk/showthread.php?s=&threadid=187 where there is currently a discussion going on about the reliablility of the Enermax PSU's.

Good Luck on your choice

[theReal]

Isn't chieftec the same as antec? Antec seem to be very good and (in most cases) have adjustable lines.

For tons of problems with Enermax and 5V, also see www.amdmb.com forums...

[rui]

Originally posted by theReal
Isn't chieftec the same as antec? Antec seem to be very good and (in most cases) have adjustable lines.

For tons of problems with Enermax and 5V, also see www.amdmb.com forums...

Could Chieftec be the same as antec?
Currently i am using the chieftec, and no problems for now. If inded they are the same, then i believe that i kept the good one ;)
But this one doesn't have adjustable lines :(

[theReal]

Well, I have a case called "chieftec cs601" and it is definitely the same that is sold as "antec cs601" in the States.

The 3V and 5V lines are not "officially" adjustable. There are two small potentiometers inside it that you have to look for (if you haven't done so already). But this is potentially dangerous, because if you turn one of these up too high, you can destroy all your hardware. I wouldn't recommend doing this unless you're having real problems with your voltages. If not, just leave it as it is.

[rui]

Thanks for the info :)
I will look in the net for possible pictures of the psu, just to know what to look for, if i decide to mess around.
Thanks again

[takeru]

i have a enermax 431watt psu. seems ok to me, considering i have 3 scsi cd drives, an ultra scsi hd, and 5 high capacity ata100 hd's running on it.

chieftec, antec, and chenming have the same cases. as to the quality per company, who knows. i think chenming is the main distributor.

[theReal]

drives and stuff does never seem to be a problem for Enermax. But there are some boards that just don't work right with some Enermax psu's
A lot of people have enermax psu's and everything is ok, but 95% of people who have massive problems with their psu's with certain Athlon boards happen to use Enermax PSU's... but I think Enermax has learned from their mistakes and make their PSU's better now (at least this is my impression)