I've been buying "stuff" to add to my two month old-new build--none of it (the new stuff) installed yet. My fascination with PSUs has grown much of late with all our discussions and, given how much money I put into the build in the first place, and what with considering adding to it, I'm thinking a PSU upgrade is needed badly. The quick and dirty:

As is:

Asus P5AD2-E Premium Wireless Edition mobo; P4 640; 2GB Corsair DDR2675/PC5400 RAM; 2 opticals (DVDRW & CDRW/DVD); 2 SATA HDDs (Raptor & Baraccuda); eVGA 6800GT PCIe; 5 case fans w/LEDs; Zalman Cu7700 HSF w/ 120mm fan; Aspire x Navigator case--stock Aspire 500 watt PSU.

The system is stable but I don't like what I see in the voltages. Here's what Sandra Lite shows with nothing else going on. Tolerances listed by Aspire for load regulation are 5% for 3.3/+5V and 10% for +/-12 & -5V: +3.3V is around 3.9 (2.4%, within tolerance); +5V is around 5.67 (off 13.4%, bad); -5V is -3.1 (off 38% very bad--can this even be true?); +12V is bouncing between 9.79 and 9.91 (off 18.4%, bad); -12V is 11.0 (off 8.3%, within tolerance). I should add that my house current is not real clean.

If all that is measured correctly, looks like the stock PSU is crap???

Want to add:

I want to add another Raptor (for RAID), a PVR (PCI TV card), and mod the fans a bit--everything is on hand now. But, this looks like a new PSU comes first. I looked at the PC Power & Cooling site. They have a nice "configurator" like Crucial does for memory. With my system as it is they recommed the Turbo-Cool 510 Express. It's $219 there and $229 at Newegg. The other options, on Saph's list, are the Antec True Power 2.0 550 ($136) and the ThermalTake SIlent Pure Power 680 (now $165 at Newegg).

I think I definitely need a new PSU. I don't think I need 680 watts. SOoo...PC Power or Antec???

Wow, funny voltage readings there! :p I'm most concerned about your +12V reading. That's probably the most important rail in modern systems! Very very bad to have that out-of-spec. Within 10% is OK, 8% is considered good, and 5% is considered highly desireable. ;) That P4 640 could very well be pulling most of the +12V power, which would explain those readings, on top of your suspect house wiring. The +5V reading is also of some concern, but actually most of the hardware that uses the +5V rail is quite resilient. Still not good to have it out-of-spec like that. The -5V reading is quite believable. That one fluctuates the most in my experience, with no real detrimental effects. It's just not that important, I guess.

Ok, the PC Power & Cooling unit would be sweet! But, the money actually could be used better. Pick up the Antec unit in addition to a good Belkin/APC uninterruptable power supply unit. UPS units have built-in line conditioning and battery back-up. That's the first thing I recommend to people trying to operate a PC in an old house. No matter how good the PSU is, bad wiring can still ruin your voltage readings. A decent PSU combined with a UPS makes all the problems go away. That's my suggestion, anyway.

How did you know my hous is old? :( The house is huge--and old. The base of the house is around 100 years, the second floor is about 30 years (was built by the then owner), and the electrical service is ORIGINAL! The electricity kind of floats all over the place. I've notice that before with other appliances and things--just never took any readings of any sort.

OK. You da man. The PC Power & Cooling unit would be sweet, and you know how I really like sweet things, but I'm going with your suggestios--The Antec and decent UPS. I wish they mad PC PSUs with built in voltage and amp meters!

It really is amazing what one can learn around here. You start preachin PSUs, Tom's runs this really neat test, I check out a PSU on one of my systems for the first time ever and get an eye opener.

You know, I've worked on military systems for 25 years as a technican and an engineer, and despite the bad press you hear all the time, they are built according to extreme specs--that's part of the reason the stuff is so expensive. When I saw these readings, I was flabbergasted. No military system would ever tolerate those variance, much less still work and appear stable.

Thanks.

I want to take the proactive approach and go for the UPS with AVR right way. I looked on Newegg and the Belkin UPS I wanted is out of stock. It just so happened that the nearby CompUSA had the same one on sale. Taling into account what I would have paid for shipping from Newegg, I only paid $9 more, not too bad.

Here's what I got: (900VA/540watts) http://www.newegg.com/Product/Product.asp?Item=N82E16842101219 The Antec will be ordered probably after I get back from my business trip. ;)

Very nice. Very good price, too. Anytime you can get retail brick-and-mortar convenience for near-Newegg prices is always a good thing! :cool:

I must confess that I did not automatically know your house was old. I was just using that as an example. I'm a hardware geek, not a fortune teller! :p

The Antec TruePower 2.0 550 has dropped in price to $110 so I was thinking of pulling the trigger now. I have two questions though. The 12v rails are rated at only 19A, is that low a rating going to be an issue for me, considering my system configuration? Remember, I'm adding another Raptor and a TV/PVR card. One variable is this is a dual +12V PSU--never had one of those before--does that mean the rails work together and one can carry excess load for the other, so to speak? Or do they work independently?

Next question is the fan--it points up? That means blowing into the 1 1/2" or so of clearance above the PSU directly at the top wall of the case, rather than out the case. That puzzles me. Much ado about nothing?

The two +12V rails are meant for different things. The +12V1 rail is for the CPU and mobo, and the +12V2 rail is for the rest of the system. This keeps them independent of eachother so that the rest of the system doesn't mess up the voltage for the CPU (this isn't really an issue yet but ATX 3.0 is smartly solving a future problem before it happens). And don't be put off by the amps. My own ATX 2.0 Antec has only a single +12V rail at 19A (pretty standard for 6 months ago). This is enough for my system because it's slightly older. So twice that will be plenty! :D

No, the fan doesn't point up. :p PSU pics always show them upside down for two reasons: 1) to show you the fan, and 2) because it's never a good idea for something to rest on top of a fan. The fan is in the normal spot when you install the PSU, sucking air up from the system and exhausting it out the back.

Upside down in the pics, eh? Goes to show you what a noob I still am :o

Having the mobo and CPU on a dedicated rail strkes me as a very good idea. I really wanted to go for the PC Power 510... hey, I'm that kind o' guy...but the prices prevailed and I pulled the trigger on the Antec today.

As always, thanks for the education. ;)