EVGA P55 Classified 200 LGA1156 Motherboard Review

Stability & Overclocking Results

With a couple of processors and stack of memory kits, this Stability Overclocking section is going to be a little cramped and somewhat unorganized. For that we apologize. But we figured it would be better to have more info than less, despite the confusion it may cause. So just bear with us, we will try to label everything appropriately.

By this point, overclocking prowess of a motherboard is almost an afterthought. P55 motherboards, like their X58 brethren, are not usually the limiting factor for BCLK with a setup on air cooling. Generally the limiting factor falls on the CPU being used. With this in mind, we still seek out the maximum BCLK we can achieve, but also put more focus on compatibility in this section than before. We'll start with some memory compatibility testing and go from there.

Mushkin Redline Ascent 3x2GB PC3-12800 6-7-6-18 (998692) Stability Testing

There was recently a discussion in one of the online forums that triple channel memory cannot be used with dual channel motherboards, such as the P55 offerings like this Classified 200 from EVGA. That is obviously nonsense because memory isn't programmed or intended to run in dual or triple channel, it runs however we tell it to run. Needless to say, we pulled out the trusty Mushkin Redline Ascent 3x2GB kit and stuck a pair of modules into the EVGA P55 Classified 200. The option to enable the XMP profile was there and as the screen shot above shows, the memory runs the XMP profile just fine.

OCZ Blade 3x2GB PC3-16000 7-8-7-20 (OCZ3B2000LV6GK) Stability Testing

Our next kit in question is the opposite of our DDR3-1600 low latency Mushkin kit just tested, it is a DDR3-2000 7-8-7 kit of OCZ Blade memory we reviewed here at Hardware Canucks a while back. Again, this memory is a 3x2GB kit intended for running on X58 triple channel motherboards and again it runs just fine at specified settings on the P55 Classified 200. Using the i5 750 processor we were able to run right up to 200 BCLK to achieve 1000MHz or DDR3-2000 for the memory with very little VTT (1.325v). This is one of the biggest differences between X58 and P55, the uncore on P55 runs on a much lower multiplier of the BCLK. Therefore we can run 1000MHz with uncore (specified by NB Frequency in CPU-Z) of only 3200MHz. On X58, 1000MHz memory required an minimum uncore of 4000MHz requiring much greater VTT. Combined with a lower uncore at high memory clocks and running only dual channel, in theory, the P55 platform is much stronger at running high memory clocks.

Corsair Dominator 4x2GB PC3-12800 8-8-8-24 (CMD8GX3M4A1600C8) Stability Testing

We now move on to a 4x2GB kit of Corsair Dominator memory that we will be using for stability testing of motherboards of the P55 platform. This kit is designed by Corsair for the P55 platform and provides a solid 8GB of memory for system use at a very respectable 800MHz or DDR3-1600. As with the Mushkin Ascent memory, we simply loaded BIOS defaults and enabled the XMP profile. With our i7 860 processor the proper 2:12 ratio was selected and the timings adjusted to the memory specifications. The only change we made was to manually lower VTT as it is set at 1.35v which is unnecessary for this CPU. In the full size screen shot we can see that with only 1.25v that we set the kit runs perfect. So keep that in mind when running XMP profiles, sometimes the VTT doesn't need to be as high as the profile sets. This will vary from CPU to CPU though so make sure to do proper testing if you lower the VTT manually. As it stands though, this kit looks to be a perfect match for the EVGA P55 Classified 200.

Corsair Dominator 4x2GB PC3-12800 8-8-8-24 (CMD8GX3M4A1600C8) Maximum Overclock Stability Testing

We figured why not try overclocking these sticks since they were in the rig. So we went back to the i5 750, and started clocking the memory. We don't think the board was the limiting factor at this point because the memory was scaling with voltage and VTT was very low still. Needless to say, those that say you can't overclock with 4 sticks of memory just aren't trying hard enough. We easily reached 180BCLK with a respectable CPU frequency. We took this overclock one step further with the i7 860 and this memory in the next screen shot.

Corsair Dominator 4x2GB PC3-12800 8-8-8-24 (CMD8GX3M4A1600C8) Overclock Stability Testing

As mentioned, we also ran this memory at specified clocks with a 200BCLK and 4GHz CPU clock on the i7 860 processor and very low volts across the board. This truly goes to show that 4 stick overclocking on the P55 Classified 200 is certainly not going to be a limiting factor in your overclock. So go ahead, load up the slots with good quality memory like this Corsair Dominator kit, and overclock all you want.

Overall Stability Overclocking

Normally we would now have maximum CPU frequency, BCLK, and memory overclocks; but with this setup we managed to combine all three into one. Essentially we couldn't get any higher BCLK with either our i5 750 or i7 860 processor (the i7 860 topped out around 210BCLK), and the memory clocks shown here (1075MHz or DDR3-2150) is only about 10MHz less than we could manage with this kit. We definitely have some work to do with the memory clocks but we absolutely refuse to loosen the important timing of Back-to-back Cas Latency in order to gain higher memory clocks like you see in the DDR3-2500 screen shots most often. B2B is an absolute performance killer and we are more than satisfied with a 1075MHz memory clock for this setup. We had to really pump the volts into the i5 750 to make it run 4.3GHz but it didn't seem to mind and the board handled it extremely well. Overall, this is a massive overclock and we are quite pleased with how the EVGA P55 Classified 200 handled overclocking on air.

We spent a lot of time with memory kits because we felt it important to show a few key screen shots like high BCLK 4x2GB clocking and the fact that triple channel DDR3 kits run just fine in the P55 motherboards, even the XMP profiles. These topics came up in the EVGA forums lately. So now that we have our overclock, let's get to some benching, shall we?