i am building a core i7 920 pc with a 4870, 6 gb gskill ddr3 1333 and 2 standard sata hdd's my psu is a rosewill rd500 psu that puts out just over 500W of power with 2 12v rails at 15 and 16 amps. As the mobo and ram are being shipped via newegg i am wondering if the psu is up to the task. I know that under load the psu shouldn't take more than about 400-450W based on benchmarks both here and around the web and I am pretty sure the amperage is fine, i was just wondering if anyone knows if this system will be stable enough for gaming for prolonged periods of time (2-4 hours). I would prefer someone experienced to please answer this.
If you just look at the specs, your Rosewill psu would be right on the edge of acceptable. The problem is that it's not really a 500w power supply. Too much of the amperage is spec'd on the 3.3 and 5v rails. You need a safety margin between power used and power available. Also, the brand is one of the worst you will find available. I would buy this:
CORSAIR CMPSU-650TX 650W ATX12V/EPS12V $100-30+ship 1/17/09 http://www.newegg.com/Product/Product.aspx?Item=N82E168...
Ya definitely go with a better PSU, especially if you can find the 750tx or 850tx for under $100, that's a very good price for those PSU's. When a PSU fails, very bad things happen to the rest of your system and you don't want to risk $1200+ worth of hardware on a rosewill. They are crap. I'd bet $$$ that PSU fails in less than 2 years, especially under the stress you will put on it with that system.
oh, btw i have been running a 4870 on a p4 setup for the last ~6 months so i was justwondering just about the processor as I know the card will run fine as it does with a modest overclock with some games (excluding Crysis). But thanks for the concern about the card
Corsair is an excellent choice. The Corsair psu's consistently earn high marks in technical reviews and comparisons. They are high quality and very stable. A lot of the veteran posters over in the psu section of the forum often recommend Corsair. Another excellent brand is PC Power and Cooling.
Most individuals overestimate power requirements. It happens all the time at this forum. Even with two 4870 video cards in Crossfire mode you power requirement is in the 600 to 650 watt range.
Yes but you shouldn't be cutting it that close. Just because your power usage is in the 600-650 range doesn't mean a 650 psu is the best choice. You will have low efficiency and high temperatures if you do go with a 650 as well as running a greater risk of a short. It's best to leave yourself 50-100w buffer IMO.