Antec P150 and Crossfire

[adamc]

After lurking around this inestimable site for over a year, learning constantly, and dreaming of my perfect build, I'm ready to start making some plans. Dreaming that long, however, leads to big dreams: a fast gaming rig, as quiet as possible.

I'm waiting for Conroe, so for now I can only really dabble around my new system's edges: HDD, GPU, case, etc. I've admired the P150 since its release, for its cable management system, steel construction, prefab HDD suspension, and particularly for its glossy white finish which matches the plethora of Mac gear populating my workspace.

I know the P180 is a more natural choice for the system I'm planning. But I just don't like it, in black or silver.

I'm planning to duct the psu in the P150, hoping I can sacrifice just one 5.25" drive bay for intake.

My biggest obstacle (that I know of) is implementing Crossfire. To start, I plan on a Sapphire TOXIC X1900 XTX, which uses liquid cooling and exhausts outside the case. Several reviews say that the cooling unit's fan performs sufficiently at low speed (2000 rpm) to cool the GPU, and Sapphire claims <18 dbA at that speed. If the fan ramps up to high during gameplay I can live with it (2500 rpm - 26 dbA). The waterblock only cools the GPU, not the PCB or memory chips, so presumably some airflow over the card is still required.

Whenever the XTX's performance becomes subjectively insufficient I'll add a second X1900 for Crossfire. Another XTX isn't an option, however, since ATI doesn't (and doesn't plan to) make an XTX Crossfire Edition. So I'll add an XT, and accept the performance hit on the original XTX, since I'll still have a net performance increase.

I haven't found any quiet XT cooling solutions that exhaust outside the case, and though some may be available at the time I add the second card, I can't count on that. So for now I plan on an Accelero X2 for the XT. So here's the final configuration:

top PCIe slot: X1900 XT with Accelero
2nd PCIe slot: TOXIC X1900 XTX
bottom PCI slot: TOXIC fan unit

One problem is getting enough intake air to the vid cards. What about ducting the lower front 92mm fan to them, and using the upper front 92mm fan to cool the rest of the case (in addition to the ducted psu)? I plan on three 3.5 HDDs in suspension, but could use notebook drives if necessary to avoid heating up the air too much before it reaches the cards, and/or to avoid obstructing airflow.

Another problem is evacuating the hot air from the XT. I could cover the ventilation grill on the rear of the case by the expansion slots (to avoid hot air intake there) and cut a hole in the side of the case next to the XT. Maybe mount an exhaust fan on the side hole? A preferable solution would be to use the rear ventilation grill by the slots as exhaust, but would that require increasing the lower front 92mm fan voltage to a less-than-quiet level to ensure positive pressure?

Incidentally, I'm not averse to replacing the Neo HE 430 and fans with more appropriate models, as you might guess from the coin I'm willing to spend on GPU's and 2.5" drives.

So, do I have a shot at keeping this system quiet, or will I have to move on to a more performance-appropriate case, like <shudder> the P180?

[hravn]

If you're willing to go crossfire/SLI, most people recommend doing it right away.. otherwise, your stuck searching for an outdated (maybe) card while you could just as easily just sell your old one and buy a new top-of-the-line single card. Hopefully with lower power draw.. (Even though it doesn't look like it if you look at Nvidias and ATIs future offerings).

Just look at the 7900GT versus the 7800GTX. The 7900GT doesn't draw as much power and is faster (and cheaper!) than the 7800GTX.

For a performance rig, I wouldn't go for a 2.5" drive... my suspended (not particularly quiet) 3.5" drives (3 of them) is completely inaudible in my P150 when they're not seeking, and very muted when they do. There is also quite a lot of space between the drives for airflow IMHO.

Getting one of the new raptors would probably be a nice addition to a power rig.

[adamc]

If you're willing to go crossfire/SLI, most people recommend doing it right away.. otherwise, your stuck searching for an outdated (maybe) card while you could just as easily just sell your old one and buy a new top-of-the-line single card. Hopefully with lower power draw.

That's a good point, and if, once this thing is built, I decide that one X1900 XTX isn't enough for playing Oblivion I'll get the second card right away. On the other hand, if I don't feel the need for Crossfire for some time, well, I wouldn't buy the second card for some time. If, when I am in the market for the second card, the more attractive option from a performance and cost standpoint is to sell the XTX and buy a new single card, that's what I'll do - and perhaps implement Crossfire at some time further still. Then I'll have paid a bit more for a Crossfire-capable mobo that I havent' fully used (yet?), and spent some time designing for quiet Crossfire (which isn't much of a loss). Which is better than paying for a second X1900 right away that I didn't need. So by designing with Crossfire in mind I preserve my option, at relatively little cost, to add a second card, or get a better single card, whichever makes more sense at that future point.

For a performance rig, I wouldn't go for a 2.5" drive...

That's good to hear, thanks!