Since this motherboard is based on nForce4 SLI XE chipser from NVIDIA, it doesn’t have an overclocking lock, read our tutorial on this subject.

The goal of our overclocking test is to check what is the maximum clock rate we can achieve with our Pentium 4 640 (3,200 MHz) CPU, which has a 200 MHz (800 MHz QDR) external bus and a 16x clock multiplier (factory-locked).

Keep in mind that for an overclocking to be considered valid, the motherboard must flawlessly load Windows and run demo 1 from Doom 3 at least four times, also without giving any errors.

ECS C19-A SLI - BIOS 1.0D overclocking options:

• External frequency: can be adjusted from 800 to 1300 MHz (QDR) in 1 MHz steps.
• PCI Express frequency: can be adjusted from 100 to 148.43 MHz in 0.562 MHz steps.
• CPU voltage: Can be set from 1.20 V to 1.60 V in 0.0125 V steps.
• Memory voltage: Can be set from 1.80 V to 2.20 V.
• LDT bus multiplier: Can be set from 1x to 4x in 1x steps.

ECS C19-A SLI has basic overclocking options. For radical overclockers, some options are missing, like chipset voltage and PCI Express voltage adjustments.

click to enlarge
Figure 8: Basic overclocking options on ECS C19-A SLI.

click to enlarge
Figure 9: Basic memory timings settings.

On the graph below you can check the maximum external clock rate we could achieve with this motherboard.

We have to make it clear that overclocking results depend a lot on the CPU that is being used, and some CPUs achieve a higher clock rate than others, so the results from our tests are relative to the Pentium 4 model we used. Other models can achieve better or even worse results that we did.

Featuring a chipset without overclocking protection, ECS C19-A SLI achieved an excellent result, surpassed by only 3 MHz by DFI LanParty 925X-T2 (Intel i925X) and achieving a better overclocking than all other motherboards based on nForce4 SLI Intel Edition chipset that we reviewed. With this motherboard we could put our CPU running externally at 250 MHz (1,000 MHz QDR), making our CPU to run at 4 GHz internally, an outstanding result (25% increase on the CPU internal clock).