To those who answered my previous question. I've opened the case and inspected the alimentator.
Right now I'm heading for the HIS HD7750, wich should be the most little/silent of the bunch.
Also, I've found it at 90E.
Here's my alimentator specs:
MAX POWER:300W
INPUT:100-240V / 6A,50-60Hz
OUT:
+12A ----- 12A
+12vB-----16A
+5,08V----13A
+3,3V----12A
+5,08VsB----2A
-12v----0,3A

The manifacturer is Delta Electronics.
According to this: http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/51543-amd-radeon-hd-7770-hd-7750-review-14.html
The maximum consume is 209W at peak.
My cpu (i3 2nd gen 2120 3,30gHZ) should run at 65W at peak.
The monitor has an external supply (?).
MB is Foxconn 2ABF
I've 6gb of RAM and a stock 500gb hdd.
All in all, the new card -should- consume a mere 20W more than the 7450...

Do you think I can buy the new card without changing the alim.?

EDIT: Oddly enough, some reviews say the card (Asus and HIS versions) consume roughly 55W under normal load and 70 in full power. That's a over the double reduction in consumes... Can anyone who uses the card shed some light on this?

Tricky, a 300w power supply is underpowered for that kind of setup.

The rule of thumb for PS picking is (or was at least last year) to note max for your video card and double it, that should be your minimum. So you would need at least a PS in the 400 w range.

The reason that the videocard is used as a reference point is that most of the time it is the most power hungry piece in a system under load.

Other forum members are more experienced with system building, so just wait a bit and you will get some proper advice.


edit: Whoa, posting from a spanish language phone into english with autocorrect sucks some major balls!

According to the website!
Changing the videocard will increase the power consuption by a whole 16W.
With the old card, the recommended wattage is 304W.
With the new card, the recommended wattage is 320W.
Now, I guess the system will never reach such values/the consumes is slightly lower (else HP would've risked by putting a supply that can't fully handle the load).
The current supply -should- survive, right? (I don't think I'll ever reach full load/all usb ports connected...)

Note that you need at least REAL 320W, and most of cheap Chinese/Taiwanese manufacturers declare their power supplies as more powerful then they really are. I have 500W Frontier, and I wouldn't put more than 75% load on it.

I'm confused.
According to this: http://www.overclockers.com/his-hd-7750 review, the CPU+GPU stress peaked the system at 142W...
Considering that the i3 consumes 65 at peak, and I've pretty much confirmed that the GPU consumes 80-ish at its maximum (Since PCI gives a max of 75W, right? And yes, the 7750 does only require that single slot for power), that all makes sense.
Am I correct?

If your current system runs fine on it, the new one would probably too. Still, I wouldn't risk using the power supply for a long time, since ones not from respected manufacturers tend not to have the efficiency and safety of let's say a Corsair or FSP PSU.