!Help Please. What Power Supply "Watts" to choose?

[GreatDaleness]

Originally posted by: alkemyst
I wish I had this info still floating in my head or had time to look it up....later on I will post it.

The important things with a PSU is not just the Wattage. Its the individual wattages and AMPs on each rail.

For the Athlon I think it's the 3.3V rail (like the pre-P4 pentiums) and for the P4 it's the 12V or something. It you search for 'infinite loop' and 'power supply' you should quickly find what numbers you need to see. This system works well for the foreign countries that have to buy their PSU's based on specs alone (as anyone should really as a Name is not going to do crap).

Å

I was just about to mention the same thing! Check the drive rail information!!

 

[alkemyst]

If you have a CPU that uses 3.3V (non-P4) then make sure your power supply provides 20 amps + for the 3.3V rail and your 5+3.3V rails add up to at least 250W together (this is a liberal measurement, but I'd try to get close esp if running high end video cards).

If you have a CPU that uses +12V I think you want at least 10A on the 12V line, but I didn't research that so much.

 

[DrLynx]

Sorry people for the delay in my post. I had suddenly become a little too busy at my work. I will read all the replies and post all my further queries/doubts very soon.

Thanks again

 

[DrLynx]

Thanks gxsaurav for your reply.

First up, I do not consider it as high setup. In fact, I am squeezing the configuration (and money) to the minimum I need and can afford. 2 Monitors is because, I have one spare 14" Samtron 40Bn from my Cyrix PC. And, 2 gamepads? No. It is one gamepad and one joystick and they are very cheap. Both together costs about Rs.1000 (US $ 20). I can't even afford a P4 But, then, even if will, I will have to buy a seperate sound card as not many Intel boards have nice ones, let alone come near to A7N8X-Deluxe's onboard nVidia SoundStorm.

But, I don't quite think so that the clock speed will not be enough, cause, of course, XP 2500+ is clocked at 1833Mhz, but, it has good L2 cache and in benchmarks really "beats" P4 2.4 in many tests. (tomshardware.com and anandtech.com). But, still, I think 1833Mhz will be enough for me, as I won't be running more than 2 apps at the same time. For example, GigaStudio 160 and Nuendo would run simultaneously in that, wouldn't it?

And, for the case, as I had said before, I am squeezing the configuration to meet my budget. So, I am looking for a case + psu @ less than Rs.2000. And, I was wondering if I could manage a 400W one withing that. You said it cost you the same amount in total. This looks cool. Can you provide more info on that?

And, of course, looks don't bother me at all! And, mediocre looking case is fine...

And, the temperature or cooling - An average one is fine for me... About 35°C is fine. Will this mean, I need no more than 2 chassis fans and 1 cpu fan (that comes with the cpu itself)?

And, I have one more doubt. A7N8X-Deluxe comes with 3 fan connectors (headers). One for CHAssis fan, one for PSU fan, and one for CPU fan. You say that the PSU will come built-in with 1 (exhaust) fan. Will this fan occupy the fan header in the mobo or will it take power directly? If it will take power directly and the one fan header (PSU) will be free, will it be fine if in that header is connected the second CHAssis fan (assuming that in the other 2 headers are connected their respective fans)?

And, thanks StraightPipe, CryHavoc, and GreatDaleness for your posts...

Atlantean - No, it is one CD-ROM drive from my old computer and 1 DVD Read + CD Read/Write COMBO drive.

alkemyst - What you had said about "drive rail" seems very important but, I couldn't understand a bit about them...

I tried Googling 'infinite loop' and 'power supply' but no avail... Does it mean that I should not buy cases that are "marked as 'for P4'"? Does 2500+ "Barton" unlike P4 as regards the power supply? I am confused... I would be very glad if you would kindly put me wise...

Waiting for all your replies...

Thank you,
DrLynx

 

[alkemyst]

Power supply's are often rated with a 'total wattage', however this is sort of meaningless as it could only be at 1amp and at 10amps the 'total wattage' drops down to nothing (big generalization, but you get the idea). Other important things are stability at a given load, temperatures and noise levels, etc. If the CPU can be called the brain of the PC, the PSU is definitely the heart.

Now top tier PSU makers will let you know the watts for the two main combined rails as well as the amps they will handle. For the athlon I believe the 3.3V rail is the most important, the 5V is the next.

Amps is the more important figure at your devices will run at a fixed voltage (3.3, 5.0 or 12V) and each one has it's own amp/partial amp requirements, this contributes to the total wattage.

An easy way to get the specs is to go to Power PC and Cooling's website and check out what their specs are for the wattage level you want and then match it to whatever PSU is available. ( http://www.pcpowercooling.com ). I choose the TurboCool 425 for my tower (3 opticals, 1 superdisc, P3-S, Radeon 8500, 4 PCI, 1GB SDRAM, 2 7200RPM hard drives and a pcmcia reader + 6 80mm fans).

Here is an interesting white paper http://www.pcpowercooling.com/pdf/Turbo-Cool_510_vs.pdf comparing two 550W power supplies that are obviously very different.

Å

 

[GreatDaleness]

You don't need to plug any fans into the MB if you don't want to, you can just plug them into the power supply directly.

If you are looking for a good case with a good power supply, but Antec. Their SLK3700-BQE model is around $90 US shipped and their Sonata is around $110 shipped. I don't know how that converts. The 3700 comes with a 350 watt power supply and one 120mm fan with a mounth for a second. The SOnata comes with 380 watt and a silent 120mm fan with a mount for a second. Ths Sonata is a silent pc case, so it has rubber mounts and a "fan only" plug that changes fan speed depending on temp.

If you already got the case, then Antec power supplies are usually expensive. Most people here seem to prefer Forton. Anand did a review of power supplies in July here. THat should point you in the right direction.