SeaSonic X750 750W 80 Plus Gold Full Modular Power Supply $90 after $15 Rebate + Free Shipping

A PSU is supposed to last for much more years than GPU or CPU. A person with OCed 7970s for now is more likely to upgrade to some even more powerful cards in the next several years.
About the link you gave, obviously it is true for a single 5870 card which the author used. but it is completely a different story with OCed 7970 * 2.

From the configuration of the OP, budget seems not to be an issue and thus he deserves a much better PSU (e.g., 80 Platinum one with higher power) than this.

In the end, why people are preferred to buy a car with 4.0L+ engine even for most of time it overkills, when budget is not a problem?

Please don't listen to this guy... He's wrong on so many levels *smh*

Please be specific. which point is wrong

A PSU is supposed to last for much more years than GPU or CPU. A person with OCed 7970s for now is more likely to upgrade to some even more powerful cards in the next several years.
About the link you gave, obviously it is true for a single 5870 card which the author used. but it is completely a different story with OCed 7970 * 2.

From the configuration of the OP, budget seems not to be an issue and thus he deserves a much better PSU (e.g., 80 Platinum one with higher power) than this.

In the end, why people are preferred to buy a car with 4.0L+ engine even for most of time it overkills, when budget is not a problem?

A person buying crossfire now will likely only continue to buy crossfire cards of the same price and power level. GPUs are not going to exceed 250 watts per GPU anytime soon, so unless he decides to move to tri/quad crossfire, his power requirements won't increase even as new generations come in.

The problem with that engine analogy is that it's wrong. Larger capacity PSUs do not give performance benefits. A larger PSU is more closely related to a larger gas tank, and paying a lot extra to have that larger gas tank. Sure, it's nice if you go long distance, but it's an extra cost that is extremely unnecessary.

Car analogies, as they almost always are, are pointless.

A larger PSU does indeed have tangible benefits, assuming that the increased capacity brings your system closer to the efficiency peak, typically ~50% load. Overall heat production will be decreased, and less power will be consumed, all other things being equal.

Whether these benefits are worth the price is an individual decision based upon usage. For a box that's always on and a peak load, this can be easily worth it well within the operating expectancy of the unit. For people who use it sporadically and under minimal load, probably not. But to say that there are no benefits is absolutely incorrect.

The Seasonic X-750 retails for $139.99



Delivered full power at 45°C
Good ripple suppression
Higly efficient
Tight voltage regulation
Nice price/performance ratio
Fully modular
Nippon Chemi-Con electrolytic caps
Semi-fanless (hybrid) operation
Seven-year warranty



The fan operation control switch should be at the front of the PSU

Seasonic's technicians had a very difficult task to complete, which was to further improve an already excellent platform. Taking into account the results I obtained by putting together this review and the results of other PSUs that utilize the new platform (Corsair AX860 and AX760), I can easily state that the new platform is significantly more efficient than the older one, and especially at lower loads does it provide tighter voltage regulation and generally higher performance. I think that designs like this one push the conventional methods based on analog circuits to their limits. Only digital control can possibly offer noticeably better results at increased cost; that is, for the time being. Seasonic has a winner in their hands with their fresh KM3 platform, and I can safely assume that they will easily lead the performance race. The new X-750 is Gold certified, but it offer efficiency that many Platinum certified units will envy given it provides super stable and ultra clean DC outputs. It can also operate in fanless mode most of the time because of its cold operation and hybrid fan-control system and has a fully modular design, which increases its usability greatly. The most important facet of all is the price at which Seasonic offers their new X-750; it is, to say the least, decent and fully justified because of the X-750's performance, its features and the long warranty that backs it up.

To sum up, the X-750's high price/performance ratio renders it a no-brainer in its category, especially if you don't want to spend more money* on a Platinum Corsair/Seasonic unit.

* After the review was posted, Seasonic informed us that the price of this unit will be increased by ten bucks, reaching $149.99 on the 1/1/2013. Unfortunately, some retailers already increased the price of the unit before the end of 2012.

You stated it was overpriced by comparing it to a psu that is not the same make or specs.

If you don't like to be called out don't thread crap.