Alienware MJ-12 Mid-Tower ATX Case with 700 Watt Power Supply

Very nice. I’m happy when Woot sells any sort of PC component.

If this had been a $30 case, I would have bought it. Just a tad to pricey for my needs, but close, Woot. Nice.

I simply have to ask.

All who are debating the cooling of the case and power supply flexibility under average and max stress on the MB and extras, Who is living in the basement ?

A heavy duty single rail will work FINE for SLI.

The ONLY thing that matters is that the supply can provide a stable amount of current to each PCI-E cable without the regulation on either going out of spec or having too much ripple or transients.

I have 15+ years of experience as an EE so I think I should know!

I didn’t realize “They MUST be” on two isolated 12v sources. What about motherboard/CPU/RAM? What about HDs/DVD-drives? Which rail does that take? I’m not sure if you clearly understand the n-rail system and its advantages and disadvantages. As stated earlier, the best power supply by PC Power & Cooling builds power supplies exclusively with single 12V rail. Their best PS (1kW) pushes massive 72A (80A Peak) from a single +12V rail. Other manufacturers build Power Supplies with numerous 12V rails, but personally, I prefer a massive single 12V rail.

Absolutely must be independent. read a manual. 2nd card will not be recognized, but go ahead and build it and see.

ps: Antec was the other one that I was thinking of. OCZ make some expensive supplies now and there are even 3 rail systems that allow for isolation of dirves. mobo’s have a completely different header conn. and of the dozen or so Ive built in SLI I generelly separate the HD and the CD on each rail with a card.

Look into Antec cases they are really nice, quiet, and solid. Just don’t fall for their rebates. It took 7 months to get my rebate.

Why just cases?

Nah, we’ll stick to Duct Tape FTW:

anyone know if it has a HD Sound Header for the front sound panel ?

You can’t build a system for less when you are spending $90 just for the case. This woot is a big rip off.

If you have 60Amp on a single 12 rail. That PSU better have some nice wires because that is a lot of current it is driving. You will also probably die if u touch it. It loses efficiency just from the wires itself unless the wire is really big.

Are the Power Supplies ATX, EPS, or both?

I’m not sure if this would be a case for those 8800gtx’s (look at the HD cage sticking out, although it does look long, but probably a standard size), but you could get this combo, sell PS for at least $100, sell case for $50 and then get a good case. :wink:

EDIT: I don’t have this case. Found pictures online - look at the links. I’m also debating if I should get it, but it would primarily be for PS. Maybe we should split the cost? :slight_smile:

Read a manual? Uh, no, you should go read a book on power supply theory and design! I HAVE.

Neither the cards nor the motherboard have any way of knowing whether or not the supply is a single rail design or a multi-rail design. All that they know is whether or not they have a PCI-E power cable connected to them that can provide enough current for them to operate stably.

Yes, each card needs an independent PCI-E cable – and each should originate directly from the 12V power plane inside the power supply. Whether or not the power plane is derived from multiple or single 12V rails (switching supplies) inside the supply DOES NOT MATTER as long as the supply can provide enough power to each card. Having independent very large bypass caps on each 12V line where they connect to the power plane is an easy solution to this.

Because we are very, very smart and we do our home work before we speak or write.

I second that-I love my Antec 900.

Can anyone confirm the number of internal bays?

All this talk of split/dual rail. I have not seen anyone mention - is the split parallel or series. The amount of inversion you get running split series rails is just too great as compared to parallel. If I recall, the inversion coefficient is like 1.9 for series and 1.1 for parallel. Can someone let me know which this is?

You can easily have 60A on a single 12V rail – however, you will NOT have a 60A load on any given cable. Each PCI-E cable is carrying nowhere near that load – and if the supply is properly designed, then it will have polyfuses on each cable to prevent overloading and melting that wire.

And, honestly, you wouldn’t need all that big a wires to run 60A @ 12V – you are only talking about 720W DC. Typical 20A (120V) house wiring is just 12AWG with 15A circuits being 14AWG (which I would personally never use except for a lighting circuit). Many typical extension cords have 16AWG stranded wire in them and they are rated to 800W.

The problem here is that people here have ZERO clue as to how power supplies are designed – the number of connectors/wires/cables have NOTHING to do with how many rails a supply has!!!

And yes, 12V @ 60A (~700W) would be quite uncomfortable and could kill you if it were to pass directly through your body for a sustained period of time. Fortunately, 12V typically won’t penetrate your skin very far. Additionally, you usually only get burns from this type exposure anyway. What you have to watch out for is 120V/60Hz AC – which your heart will try to sync up with and often causes it to go into v fib. Similarly, high voltage is painful but not that dangerous unless there is a lot of amperage behind it (if you want pain, forget to discharge the DAG line on a 32" CRT TV chassis sometime … been there, done that, won’t do it again).

There’s no way that’s a true 700w PSU for that price. Prolly some lightweight phony.