Building a Computer/Power Supply Requirements

[pcguideuser745]

I have been looking around for several days now, but I have not been able to find a power supply that would meet the requirements for the new system I am building. I will list below the components I have compiled so far (feel free to comment):

Processor : AMD Athlon 64 X2 4200+ [Socket 939, 2.2GHz]
Video Card : GeForce 7900 GT [PCI-E x16, 256MB]
Motherboard : Abit AN8 32X
System Memory : 1GB OCZ Dual Channel DDR400 [2 x 512MB] Model: OCZ4001024PDC-K
Power Supply : ???
Cooling System : Zalman Reserator 1 Plus
Hard Drive : 160+GB, SATA. Exact model yet to be determined.

Essentially, I am attempting to build a fast, but quiet computer, hence the passive water cooling option I selected. (And therefore, I would be looking for a fairly silent PSU as well.)

According the various sites, in order to run a GeForce 7900 GT, I need a 350W power supply, with 20 amps on the +12V rail. I have been unable to locate a power supply that meets this requirement, while at the same time not being too expensive. I have found power supplies with 18 amps on the +12V rail, but I am unsure if that will be enough to run the system I have configured above, plus some other devices (floppy drive, cd-rom, etc.)

For example, I have been eyeing Thermaltake's 430W power supply (model W0070). It is a relatively cheap PSU, however, it comes with only 18 amps on the +12V rail. Will something like this be sufficient to run the system I have outlined above? If not, then can anyone recommend any?

Thanks in advance. Again, feel free to comment on my build.

[jlreich]

For example, I have been eyeing Thermaltake's 430W power supply (model W0070). It is a relatively cheap PSU, however, it comes with only 18 amps on the +12V rail. Will something like this be sufficient to run the system I have outlined above? If not, then can anyone recommend any?
That won't do for a modern system. I have two of those PSU's and they are pretty good PSU's for older systems, particularly for the price.

You need a PSU with 2 12v rails to power a modern system, especially an X2 and a 7900GT. I would go with nothing less than 500W with at least 18A on each 12v rail for your system. Higher watts as budget allows.

I hate to say it but your looking at spending at least $80-$100 for a good PSU to power that system properly. ;)

[pcguideuser745]

Thanks for the reply.

Wow, I honestly did not think I would need that much power to run my system.

Perhaps something such as Antec's Truepower 2 480W PSU (http://www.newegg.com/Product/Product.asp?Item=N82E16817103930) would suffice for my system? It has two separate +12V rails at 18 amps each. I'm thinking that it's a pretty good deal too, as I can get it for between $80-$90.

[jlreich]

For $7 more after free shipping the 550w is a better deal. http://www.newegg.com/Product/Product.asp?Item=N82E16817103932

It's only a one day sale, so it will be $14 more after tomorrow sometime. Still though I would feel more comfortable with 550W running that system.

I have a 550 running my AMD64 3000+/6800GS system.

[pcguideuser745]

Awesome, that looks like a fantastic PSU. Yes, I think I'll go with the 550W version then. Thanks again jlreich

Oh and one last thing. What is the difference between Antec's "Truepower 2.0 550W" and their "Truepower 2.0 EPS 12V 550W"? (Part Numbers TPII-550 and TPII-550 EPS12V , respectively)

[pcguideuser745]

After a little more researching, I seem to have stumbled upon Thermaltake PSUs. Would something like their W0073 (http://www.thermaltakeusa.com/product/Power/PurePower/w007374/w007374.asp) model suffice for power requirements? It is a 520W power supply that has two separate +12V rails, each with 15 amps.

[jlreich]

That would be good if it wasn't modular. Stay away from modular PSU's. It seems like a good idea but you really want it to be hard wired.

You are in the right frame of mind now though. Stick with good names like Thermaltake, Antec, Seasonic and a few others and dual 12v rails and you will be in good shape.

I am not sure what the EPS means to be honest. The only difference I can see is it seems to have an 8pin auxiliary 12v connector for the CPU that can be split into two 4 pin connectors.

Anyone know about the new 8pin connector? :confused: Is this to power the new multi core CPU's coming out soon? I will have to look into it.

[pcguideuser745]

If I might ask, what is the problem with modular power supplies? I have also been looking at Thermaltake's W0057-01 power supply (http://www.thermaltakeusa.com/product/Power/PurePower/w0057-01/w0057-01.asp) . It offers a total of 500W of power, with dual +12V rails, each providing 18 amps. However, this is also a modular power supply...

[jlreich]

Well first off it seems what I am finding out about EPS PSU's are they are not interchangeable with ATX PSU's, so scratch that one for certain. :o Seems they are for EPS mobo's, seems mainly for certain types of server boards. And it isn't new at all. :o

If I might ask, what is the problem with modular power supplies?
Any time it's not a direct connection it increases the chance for a problem. Also there have been reports of people having problems with modular PSU's. It's just something that's best to avoid. Especially with something as important as a PSU. ;)

[pcguideuser745]

I see. Well I suppose that's a risk I'm going to have to take. And with that, I have a final list of the components I will be purchasing for my new system.

Processor : AMD Athlon 64 X2 4200+ [Socket 939, 2.2GHz]

Video Card : GeForce 7900 GT [PCI-E x16, 256MB]

Motherboard : Abit AN8 32X
Okay, so all the reviews haven't exactly rated this to be the best motherboard. It's got some questionable placement of the power connectors, and it doesn't have any outstanding features when compared to other manufacturers. But the passive chipset cooling is why I chose this board.

System Memory : 1GB OCZ Dual Channel DDR400 [2 x 512MB] Model: OCZ4001024PDC-K
I actually wanted to get 2GB of RAM, but unfortunately the price for 2GB of RAM would exceed my already-tight budget. So I'll have to make do with just 1GB.

Power Supply : Thermaltake Purepower 500W (Model: W0057-01)
Like I said, I'll have to take my chances with this modular power supply. I was also considering the W0073 model, even though that too is a modular PSU, but the extra 3 amps this PSU offers on each of the +12V rails gives me a little more peace of mind.

Cooling System : Zalman Reserator 1 Plus
After several months of having to deal with the annoying sound my computer has been making VRRRRRRRRRRRRRRR...I really, really want a low noise computer, hence the reason why I opted for passive water cooling. I was debating whether to go with this or some Asetek water cooling, but I decided to go with this.

Hard Drive : Maxtor 250GB Ultra-ATA
I'm gonna have to stick with my old hard drive, as getting a new one would exceed my budget.

Well thanks again to all who helped answer my questions. It's very much appreciated. Again, feel free to comment on my build.

[rond36]

Well first off it seems what I am finding out about EPS PSU's are they are not interchangeable with ATX PSU's, so scratch that one for certain. Seems they are for EPS mobo's, seems mainly for certain types of server boards. And it isn't new at all.

That is not entirely true, ATX EPS+12V PSUs are completely compatible with ATX 2.0 (24 pin power connector) motherboards. Before the ATX 2.0 specification they were not because ATX 1.0 and ATX+12V used a 20 pin power connector and the EPS power supplies have a 24 pin power connector (wich is also part of ATX 2.0) but you can get an adaptor to make them work. Most ATX EPS+12V power supplies come with a 24 pin to 20 pin adaptor or the extra 4 pins snap off the end of the connector. The only other differences are the 8 pin 4X2 and a 6 pin 3X2 connector and the duel +12V rails which is also part of the ATX 2.0 spec. Some ATX EPS+12V power supplies have as many as 4 +12V rails.

My power supply is an ATX EPS+12V PSU and my motherboard is ATX+12V(20 Pin)

The PC Power & Cooling TURBO-COOL 850 SSI T85SSI SLI, EPS12V, SSI 850W Power Supply
and the
PC Power & Cooling TURBO-COOL 1K SSI T1KSSI SLI, EPS12V, SSI 1KW Power Supply are EPS power supplies along with several others.

The biggest difference between ATX 2.0 and ATX EPS power supplies is EPS PSUs are built to a higher quality standard because they are made for servers and workstations.

While ATX EPS power supplies are compatible with ATX 2.0 motherboards, ATX 2.0 power supplies are not compatible with morherboards that require an EPS power supply because they lack the 8pin and 6pin motherboard power connectors

Look at the Tom's Hardware PSU stress test out of three that made it through within specs two were EPS PSUs The PC Power & Cooling TURBO-COOL 850 SSI T85SSI SLI, EPS12V, SSI 850W Power Supply and the PSU in my signature and I'm sure the 1KW would have made it too.

[jlreich]

Thanks for clearing that up rond36. That's the first time I ever noticed EPS, and the information I was looking at is a few years old (before 24pin on ATX mobo's).

pcguideuser745 the list looks fine to me. I always go for one of the big names like Corsair, Kingston, and Crucial for ram, but OCZ is fine if that's what you want. :)

[saphalline]

Just FYI, ATX 2.0 is not the new spec for PSU's. It's ATX 3.0. Or you could list it as ATX +12V 2.0. It's all a little confusing, but don't mistake them. ATX 2.0 still uses the 20-pin main power connector, and was called ATX +12V (version 1.0) because of the addition of the square 4-pin +12V connector following the release of the P4 in 2001.

That's all I had to say.

[pcguideuser745]

I have been thinking of adding in another GeForce 7900 GT graphics card so that I can run two of these in SLI.

Will my power supply be able to provide enough power to my system? And will my CPU be too much of a bottleneck?