ECS L4S8A (SiS 648): Value P4 Performance

ECS L4S8A: BIOS and Overclocking

As is not unusual with modern-day performance motherboards, the ECS L4S8A utilizes Phoenix Technology's Award BIOS.

The PC Health section of the ECS's latest L4S8A BIOS contains an average amount of info.

Here you'll be able to find readings on Vcore, PSU readings (all rails), battery voltage, CPU temperature, system temperature, and different types of fan speeds for each of the three fan headers on the board. We see that the reported temperature as read by the PC Health section in this Nov. 6th BIOS hovers around 36-38C, which is only a couple degrees lower than what the norm is for this particular CPU.

We weren't able to do a whole lot of tweaking in the Advanced Chipset Features section of this BIOS, but at least we were able to adjust Command Rate and DRAM timing mode (although this is pretty normal for SiS 648 boards).

You're able to adjust CAS Latency, Command Rate, and DRAM timing mode only. We would have like to have seen other timings as well, but they don't affect performance all that much, so we aren't too disappointed. Interestingly enough, there are DDR400 and DDR400V timing modes available after Ultra mode in the BIOS.

Unfortunately, these options didn't do anything for DDR400 performance, as we were unable to operate even one stick of Corsair XMS memory at 400MHz no matter what timings were used. DDR400 and DDR400V timing modes worked well with memory running at 333MHz, but in both cases there was a performance drop versus Ultra timing mode, making it pointless to use the DDR400 and DDR400V modes.

There are a ton of memory dividers with the November 6th BIOS; We have found this to be the case with several SiS 648 boards, including the famous Gigabyte 8SG667.

Unfortunately, we were unable to run even at 400MHz with any real reliability and in general, these memory dividers are a complete waste on the L4S8A. The best thing to do if you plan on running this board in spec is to run your FSB at 133MHz with memory running at 333MHz.

The voltage adjustments available in the BIOS were pretty weak with this board. VDIMM was only adjustable as high as 2.62V in 1.2% and 2.0% increments. In reality, this really isn't too terrible, as most memory overclockers usually don't need more than 2.6V. However, it's still a limitation, even though this board can't handle high overclocked memory speeds.

Vcore is adjustable only as high as 1.575V in 1.0% and 2.0% increments. In reality though, the actual max Vcore will only run at 1.525V or so. This is due to the fact that this board undervolts quite a bit; in fact, between 1.44-1.45V when Vcore is set to normal (1.5V is the default Vcore for all pre-C1 stepping Northwood Pentium 4 processors). This is actually quite a limitation for overclockers, as 1.525V isn't that much at all. We would have been satisfied with 1.6V (which is pretty safe).

Thankfully, ECS included an AGP/PCI lock running at 66MHz/33MHz in their latest BIOS update dated November 6 of this year. Previously, in the October 10 BIOS, there was no AGP/PCI lock option. This is a very welcome feature to have for all overclockers, as it protects your AGP and PCI cards from running at too high a frequency, which could potentially damage those cards.

The ECS L4S8A was able to rack up some very impressive FSB overclocking results (for a SiS 648 motherboard). However, it should be noted that this overclock was using a 1:1 divider, and in general performance wasn't as proportionally better as we would have liked compared to stock and officially supported 133MHz FSB and 333MHz memory performance numbers:

With this setup we were able to push the L4S8A to 152MHz FSB. This is the best overclock we've seen out of any SiS 648 motherboard. However, we were forced to run at a 1:1 divider, meaning memory ran no higher than 304MHz effective clock. While this isn't too bad, we were able to run the SiS 648-based Gigabyte 8SG667 at 150MHz FSB and 400MHz effective memory with the exact same setup (we were even able to reliably reach 422MHz memory clock). Therefore, we still think the 8SG667 is the best performer/overclocker out of all the SiS 648 motherboards we've tested so far, and in its highest overclocked state, the fastest SiS 648 motherboard on the market.