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Untapped Potential - SLI Power Supply Help
Dear Mad Mod Mike,
I recently upgraded my PC to SLI after seeing the amazing frame rates produced by my friend’s Dual GeForce 7800 GTX’s. BUT, I’m having some BIG problems...
My friend helped me with the first issue (I couldn’t even boot up my new system) by suggesting a new 500W power supply (I had a very generic 300W power supply from my old system). Everything seemed to be working fine, but now my system crashes every time I play my favorite game.
This is obviously really frustrating for me since I’ve spent a ton of money on this upgrade and my friend’s system works so much better. Pleeeeeeeaaaassse HELP!!
System Specs:
AMD Athlon 64 FX55
DFI LANPARTY nF4 SLI-DR
2 BFG 7800 GTXs
2 GB Corsair XMS PC-4000
Creative SB Audigy 2 ZS
Maxtor SATA RAID 160GB HDD
XYZ1 500W PSU
Windows XP Pro SP2
Thank you,
Untapped Potential Cleveland, OH
Not to worry my friend. Your SLI system will be tearing through your favorite games in no time!
After analyzing your system specs, it appears that you are putting water into your Ferrari's gas tank, rendering it nothing more than a Pinto on cement blocks! Your friend was a pretty smart dude to suspect the power supply as the main culprit, since this component is a common cause of system instability, often overlooked by gamers.
However, your computer-savvy friend didn't tell you everything you need to know about power supplies, and it led to an ill-advised purchasing decision. Listen close, and you won't make this mistake twice...
When buying a power supply for gaming, it's important to look not only at the total output (in your case 500W) but also at the output that can be supplied on the 12V line.
Because you have 3 very important components (your CPU and two GPUs) drawing power from the 12V line, this line is critical. Looking at the specs of the 500W power supply you purchased, there is only one +12V line, giving you a total of only 15A.
For your SLI system, you should have a power supply that can supply 30A (twice as much!) from the 12V lines.
If this is way over your head and too technical, don't sweat it - NVIDIA has a certification program that qualifies power supplies (SLI-Ready) that ensure 500W total output, 30A on the 12V rails, and 2 PCI Express connectors for your dual graphics cards.
The NVIDIA SLI-Ready certification process also tests to ensure power supplies meet the manufacturer's published specifications. I won't even tell you how many power supplies I've seen that don't even meet the specs on their own box! A good rule of thumb for any upgrade is to make the NVIDIA Certification page your first stop. Let them do the homework for you and your upgrades will go a lot smoother.
Bottom line: Use an SLI-Ready power supply from the NVIDIA certification list and avoid having a very expensive paper weight on your desk. POWER-UP WISELY.
