 Now, as some of you may know, Intel's P67 platform has only 16 PCI Express lanes available for graphics configurations. Well basically available for your main two PCIe slots here. I'm going to show you a board that doesn't have stuff installed on it. So you've only got 16 PCI Express lanes for this one and this one, which means you can either do 16x and actually I think you can make it run at 1x, so maybe 17 PCI Express lanes, not the point, okay? So it's either 16x or 8x, 8x on these two. Now some Sandy Bridge boards, P67 boards that is, have a third PCI Express 16x physical slot. This isn't the only one, but this is the ASUS P67, P8P67 Deluxe and this one does have a third slot. So because there's only 16 lanes running off of the CPU itself for those graphics card slots, where does this extra PCIe 16x slot run off of? Well, the answer is that this is actually only a PCIe 4x slot and it actually runs off of the chipset. So there is an inherent delay. Now the chipset does get a fair bit of bandwidth to the CPU itself, but that PCIe slot is actually not tied directly to the CPU the way that the other ones are. So I had someone ask me a question, what if you're running something like this, like an OCZ RevoDrive X2 240 gig? I happen to have one handy. Is there a performance difference between running it off of a PCIe slot that's running off the CPU versus running it off a PCIe slot that's running off what is essentially in archaic terms the South Bridge? So this video is an attempt to answer that. I'm just going to be using Crystal Disk Mark to keep things simple. And so I'm running five times the entire test. I'm running it over a 4 gig span of the drive. And here are my results, running it in the, in theory, faster PCIe slot. And now I'm going to run it in the other PCIe slot and see what happens. Well, it would appear that I have my answer. The sequential numbers are oddly enough very, very close for reads. This is running off of the chipset PCIe slot. And then the screenshot I have here on the left is running off of the CPU PCI Express slot. So the sequential reads are pretty much within margin of error. The sequential writes look to be a little bit higher on the chipset PCI Express slot for whatever reason. And then moving down into the random reads and writes, it looks like for reads we're pretty much within the margin of error, but then for random writes, for whatever reason, actually well, random reads here, you know what? Overall random performance seems to be higher on the CPU PCI Express versus on the chipset PCI Express. And that does seem to be like a noticeable overall trend. So, yeah, I'm not sure why that would be. Maybe it's to do with the latencies involved. Although storage latencies are usually, what I should say is chipset latencies are usually nothing compared to storage latencies. So I wouldn't have thought that it would affect it that much. But it looks like for whatever reason, the lower latency between the CPU and this PCI Express slot versus the CPU to that chipset to that PCI Express slot seems to give us slightly better performance in random reads, both in a light workload scenario as well as in a heavy workload scenario. So thank you for checking out this little Linus Tech Tips video about the Revo Drive X2 on the P67 chipset. Don't forget to subscribe for more unboxings, reviews, and other computer videos.