Suggestion for alternate PSU. EDIT! :It's my VGA card :(

Hi guys.

So, I think my PSU is borked. It's been raining like crazy the past few weeks with thunder and all that so I guess that's why.
The PSU I'm currently using is a Seasonic X650 Gold Modular 650w.
Since today, everytime I try to startup my PC, it flickers for half a second and then dies again. The light turns on, the CPU fan moved but that's it, just half a second.

So yeah, my main guess is the PSU. I've yet to try out with another PSU because I don't have a spare one to test with.

My specs :
Intel Core i7 2600K @ 3.40GHz
ASRock P67 Extreme6 (CPUSocket)
1279MB GeForce GTX 570 (MSI)
2 HDD's
1 DVD ROM

I am ready to buy a new one because I couldn't find the receipt nor the guarantee thingy for the PSU  
Problem is, I'm kinda short on cash. And last time I checked, the PSU I'm using is still around (when dollarized) $160, which is too steep for me.
This rig is my first high-end PC so I've never tried any other kinds of PSU. My friend recommended Corsair, Thermaltake, or Cooler Master.

My questions are :
1. Is it the PSU? (it's most likely tbh)
2. Is there anyway I can prevent this from happening again? I do use a stabilizer, but alas..
3. Any recommendations for a new one? A cheaper alternative please  
4. Is 650w too big for my current spec?

Big THANK YOU in advance.

EDITED for the 4th question

ADDED EDIT : Turns out it was my VGA card that was borked. So I've no choice but to buy a new one. The only one I can afford right now is
Gigabyte Geforce GTX660 2048MB DDR5 - GV-N66OC-2GD
And I'm going to buy a UPS to prevent this tragedy again.

Questions :
1. Alternative VGA? That is not far (performance wise) from my old one "1279MB GeForce GTX 570 (MSI)"
2. What wattage capacity UPS should I get? and a recommended brand would be nice. The store guy told me to buy a ICA CP1400 VA + AVR

I will be scouring the net to find a good alternative, but any inpputs from you guys would be very2 helpful too.

Thank you in advance.