Overclocking the Ultimate SLI Giveaway PC

One lucky FiringSquad reader is going to be taking home a really nice PC this holiday season. Earlier this week we went over the specs of the Ultimate SLI giveaway machine. Today it’s time to build the system and overclock it!

In case you missed the first article, we’ll quickly list the system specs:

NVIDIA SLI Giveaway PC Components

CPU: Intel Core 2 Quad Q6600
GPUs: 2x EVGA e-GeForce 8800 GTX
Motherboard: XFX nForce 680i SLI
RAM: 2GB OCZ PC2-8500 SLI Edition DDR2
Hard Drives: 3x Western Digital Raptor 150GB
Chassis: Cooler Master Cosmos 1000 CSX Limited Edition with custom paint job and individual serial number “NV0003”
PSU: PC Power and Cooling Silencer 750 Quad
OS: Windows Vista Ultimate

We’d once again like to thank our sponsors CoolerMaster, EVGA, Microsoft, NVIDIA, OCZ, PC Power and Cooling, Western Digital, and XFX for providing the components inside our giveaway PC. We enjoy giving back to our readers whenever we can and all of our sponsors play a pivotal role in making this happen. The giveaway system is now fully built and waiting for its new owner. There’s still time to enter for a chance to win this system, so head on over to the NVIDIA SLI Giveaway Cluster today!

Overclocking the system

While this system is a blazing performer at stock speeds, we couldn’t help but see how far we could push it with a little bit of overclocking. The BIOS on our XFX nForce 680i motherboard is loaded with options for overclocking, and our SLACR Core 2 Quad Q6600 CPU is based on Intel’s newer G0 stepping, so we were eager to see how far we could push the chip. For even more performance, we also OC’ed the EVGA graphics cards and the OCZ DDR2 memory as well. First the CPU…

As most enthusiasts know by now, Intel’s Core 2 line of CPUs have developed a strong reputation for being really good overclockers. The dual-core CPUs scale a little bit further than quad-core, but even the quad-core processors like our 2.4GHz Q6600 can hit speeds well in excess of 3GHz. Therefore 3.0GHz was the first target we shot for and our Q6600 chip was able to run at that speed without any issues. From there we OC’ed in 100MHz increments before we finally settled on 3.3GHz (9.0x367) at 1.4V.

We could actually boot into Windows Vista and run many apps at speeds of 3.45GHz, but it wasn’t completely stable at 1.4V of juice, and we didn’t want to increase the voltage any higher. Also keep in mind that we’re running with the stock Intel heatsink/fan unit for cooling. With better cooling we probably could have squeezed even more MHz out of the processor but we didn’t want to press the issue. After all, 3.3GHz is a nice improvement over stock. We went ahead and validated our results with CPU-Z here.

You can also see at the CPU-Z Validation URL that we were able to push our OCZ DDR2 memory to 1172MHz, an improvement of 106MHz over the stock 1066MHz speed that the memory is designed to run at. We hit this speed at the memory’s rated voltage of 2.3V; we didn’t attempt to overvolt the memory or increase the timings. With more voltage and/or higher timings, we probably could have hit even higher memory speeds but we wanted to stick with the stock settings here.

The final component that we overclocked were the EVGA e-GeForce 8800 GTX graphics cards. Here we were able to push the cards up to 630MHz on the graphics core and 950MHz memory. This is an improvement of 9% over the stock GTX’s 575MHz core clock speed and 5% on the memory.

Armed with these higher speeds, we were eager to see how the stock 2.4GHz system compared against the overclocked configuration. We ran a couple of tests from our usual suite of benchmarks to gauge the performance improvement.