I bought a ASUS CM6870-US-3AD recently and found the graphics card , Nvidia GT 620 2GB to be under powered for even something like the sims. So I want to upgrade to a GT660 but the PSU is only 300 watt.. Some on here suggested getting a antec or seasonic PSU but how do I know if they would fit my system and not burn it up.. Are these the only two choices I have??
No, you have other choices. Antec and Seasonic are good brands, but there are plenty of other good brands out there as well. I've had good success with Corsair PSUs, as well as Cooler Master and Antec. Go to Newegg and look through the popular PSUs listed there. Read the reviews and make an informed decision. And always keep you receipts.
The PSU should not "burn it up". It will only supply as much power as the system needs, so don't be afraid to go to a higher power (measured in watts) unit. What you should be careful of is making sure your case has enough airflow to cool a higher powered graphics card. Most cases will be fine as long as you have a few fans installed.
PSUs follow a common formfactor. There's some variation in depth but the height, width, and mounting screw positions are specified by the ATX12v 2.x formfactor to which they all conform. You should be able to replace that 300 watt PSU with a 500 watt one quite easily. PSUs that are rated at 1,000 watts or more may be a bit deeper, but should still fit.
One thing that you will have to be wary of is the airflow. Some PSUs have the air intake on the bottom, while others have it on the rear. Some cases may secure the PSU in a way that blocks airflow to the bottom of the PSU so be careful of this.
As for PSU brand, Sea Sonic is the best but also demands a price premium. Enermax is another reputable manufacturer which is a bit more affordable than Sea Sonic. Corsair, Antec, and XFX don't manufacture their own PSUs but only source them from reputable OEMs such as SeaSonic, Enermax, Delta, Flextronics, and CWT. Any of those listed brand names will do you well.
Other rebranders such as OCZ, Thermaltake, Cooler Master and Kingwin are all over the place.
i suggest corsair cxv2 500w.it is enough for gtx 660
+1 The corsairs are nice units for the price, I just got in a 430, 500 and 600 CX imo best budget units when you can get them with a few bucks off code and/or MIR. Corsair has been excellent with their rebates in my experience
Wow, appreciate all the info everyone has provided.. Makes me feel more comfortable about my future PSU upgrade.. I'm leaning more towards PSUs of good standing and powr savings so I got some research to do. My only other concern is rewiring a new PSU into my case a major hassle? And some asked about my case, I feel it's fine on airflow.
last question.. I notice a lot of variations in voltage ... they will say ATX 12V 2.2 or 2.3 or 2.9.. do i need to worry bout that end number\?
That's the specification number.
The original ATX formfactor put most of the power on the 5 volt rails as 12 volts was only used for fans and motors (for hard disks and optical drives). Around the year 2000 the industry switched to 12 volts as the primary DC level and renamed the specification to ATX12v with the first revision being 1.0
Since then, the ATX12v specification has undergone several revisions with the most recent being ATX12v 2.3 in 2007
It's unlikely that you'll find anything else on the shelves, so I wouldn't worry about it.