The conventional secondary output for 5V and 3.3V is as shown in the above figure. +5V and +3.3V share the same secondary winding but, with different control methods.

+5V and +12V are group regulated and the cross regulation greatly depends on the design of coupled transformer L1.

The +3.3V, on the other hand, uses magnetic duty ratio controller for independent regulation. Whenever system draws big current from +5V and +3.3V, there will be loss across D1, D2, D3, D4, L1, L3, and small amount on L2, L4. The forward voltage drop of schottky diode D1 ~ D4 is proportional to forward current. Therefore the loss is high as current increases.

By using VRM, we can eliminate diode D1 ~ D4 and L1, L3. VRM draws power from +12V lines and step down to +5V and +3.3V using high side MOSFET and low side MOSFET. The MOSFET on impedance is very low ( in miliohm range ). Hence, the efficiency is higher and tighter regulation is possible because it is locally regulated by VRM controller. VRM output requires low ESR capacitors as it affects the output ripple voltage. The entire VRM circuits is on the modular connector PCB. 2 toroidal coils are the output inductor. All capacitors are chemicon PSA series.

This post has been edited by kisuke_77: Feb 6 2010, 08:53 PM

how much is the cost? where can to get it?

high temperature electrolytic capacitors, dual sided PCB and even scratch resistant power supply case coating make this one of the more advanced power supplies to come out in a long while. definitely not a cheap buy but worth the bang for the buck.

It costs about S$265 in Singapore ... That would be around RM650 !

u quite good on understanding about psu..
why don't build one, should cheaper i guess..

Understanding how it works is easy... But, designing a PSU requires experience and skill. I am not up to that level

if not mistaken,
corsair's psu are made by seasonic right

not all.. but those single 12v rails yes..

this is the few 80plus gold... nice review...

So X750 is competitor to Corsair HX750 but I still prefer HX750 over X750.

1) noise level & performance HX750 = X750
2) HX750 has longer, thinner, and more cables. X750 is badly sleeved aiyoyo
3) HX750 has 7 years warranty, RM630 vs X750's 5 years RM600
4) X750 looked fat & short

Both are good PSUs, base on Synchronous Rectification Forward Converter ...

But,
(1). Seasonic uses Sanyo Denki PWM Fan ... HX750 - Yate Loon
(2). Seasonic uses all Japanese Capacitors ... HX750 - some are non-Japanese capacitors

VRM ouput capacitors in HX750:


It it up to individuals ...

This post has been edited by kisuke_77: Feb 7 2010, 09:39 AM

yup, its 100% modular, like decathlon series

plus the connector is a female type

which is hella easy to find spare cables of ur own

& sleeve em with murdermod sleeve

HX850
http://www.jonnyguru.com/modules.php?name=...=Story&reid=153

X650
http://www.jonnyguru.com/modules.php?name=...=Story&reid=169

dont think latest corsairs are oem by seasonic anymore, the hx620 and 520 yes they are made by seasonic.

Since TX series onwards up till the HX650W,750,850 all by Channel Well.

and checkout how well the X650 Unit can deliver the voltage, guess X750 will provide the same performance as well...

What I think about corsairs are TX and HX series all sleeved more nicely compare to X750.

Personally i like the Corsair sleeving, but i like the X750 temperature activated fan

ace so this one worth to get or not? i am using pcp610 la. thinking to upgrade to this unit.

yeah, kinda agree with you, its dead silent (0 dB, no PSU will quieter than it) when system are idling.

i even can game without have the fan to spin, but stress test time it will spin. (on stock settings)

Errr....I used to have a FSP Zen 400w passive PSU inside got no fan one, that one is total silent

Anyway, this is one good quality psu, inside almost no wires

aiyoyo i still confused to get x750 or hx750 la.

one comment for the box....

it doesn't have handles (pemegang)....

Trust me, even got handle, u also scare the weight will damage the box by pegang it