A few PSU questions

[Madrhetoric]

First, thanks to anyone willing to read this and help me out. I've already gained a huge amount of knowledge from this site. Anyway...

I recently placed an order for a brand new system. Here are the specs:
CPU: Intel® Core™ i7-920 2.66 GHz 8M L3 Cache LGA1366
Mobo:Asus P6T Intel X58 Chipset SLI/CrossFireX Mainboard Triple-Channel DDR3/1600 SATA RAID w/ eSATA,GbLAN,USB2.0,IEEE1394a,&7.1Audio
GPU: NVIDIA GeForce GTX260 CORE 216 896MB 16X PCI Express
PSU: 800 Watts Power Supplies (CyberPowerPC XF800S Performance ATX 2.0 Power - Quad SLI Ready)
RAM: Corsair Dominator DDR3 1066


My gameplan was to eventually overclock the CPU to 3.66Ghz and get a second 260 to run in SLI.

I was hoping someone could tell me if my PSU will handle these changes. Doing some searching online, I think I'd be fine running two 260s SLI with the 800 watt PSU. I'm just not sure how big the power increase will be with the CPU overclocked as well. Should I be OK or are there foreseeable problems?

Thanks again for any input.

 

[flyin15sec]

800W is fine for that setup. Un-oveclocked you will only use about 370W on load. With SLI, its ben tested to be about 500W on load, that gives you a range of 140W head room for an overclocked i7 920, at 80% efficiency.

Bear in mind testing was done with Prime95 and Furmark running, which is unlikely that any game will stress a CPU as much as Prime95 while gaming. So you're wattage draw will be lower than tested.

 

[theAnimal]

Get a good quality PSU instead. Corsair TX750 or 850, or HX750 or 850.

 

[mlcloud]

Well, the Cyberpower PSU has 50A on its 12v rail for 600watts (480 at 80% efficiency)... which might be BARELY adequate for an i7 and 2 260 GTX sli's. Someone else who has the exact numbers and power consumption for the i7 and 260 will have to find out if 50A is enough... but really, You might wanna just grab a 750TX from Corsair.

 

[Madrhetoric]

Will I be fine with the current psu if I don't overclock the i7 and just add another 260 in SLI?

 

[Madrhetoric]

http://www.tomshardware.com/reviews/overclock-core-i7,2268-10.html

So at 2.66Ghz I'm using 213 peak and at 3.66Ghz, 265. Like mlcloud said, dual 260s should require a 550watt psu max. So hitting around 600. Hopefully I can a psu on the cheap once I need to do this anyway.

 

[theAnimal]

Well, the Cyberpower PSU has 50A on its 12v rail for 600watts (480 at 80% efficiency)

That's not how the efficiency works. 600W @80% means it will draw 750W AC. (Although if the 600W is rated @25C which is likely, then it will be less at operating temperature.)

 

[mlcloud]

That's not how the efficiency works. 600W @80% means it will draw 750W AC. (Although if the 600W is rated @25C which is likely, then it will be less at operating temperature.)

And that's what I get for writing this stuff after final exams. Soz 'bout that.