While X38 is now making its way into the retail market slowly, P35 has been here for some time, long enough to prove itself to be a great successor to the P965 series chipset. This is especially because it has both DDR2 and DDR3 support, and in some cases you can even get boards with both DDR3 and DDR2 memory slots onboard. You simply can’t use them at the same time, but one thing is for sure, it makes upgrading a lot easier. This is no surprise as Intel has done this before with the 915 chipset which gave both DDR and DDR2 memory support on a single chipset.
So far we have seen a lot of P35 boards come out, some good, some bad and some that fit the extreme users bill. ASUS, GIGABYTE, MSI and ABIT have been the biggest players so far, but none have done what ASUS has managed to do here.
While the P35 chipset is supported by ATI/AMD to run Crossfire, the way it is implemented is extremely inefficient. On the P35 boards (the same as the P965 series), Crossfire is set up on a 16/4 basis, what does this mean? We’ll explain quickly now.
Simply put, you need two PCI Express x16 slots, while they are physically x16 in length they can run at any speed from x16 all the way down to x1 speeds, depending on how many lanes are routed. Unlike the 975X chipset which has the ability to automatically route 8 of the 16 lanes to a second PCI Express x16 slot, the P35 has to keep all the lanes to the first graphics slot, so how does the second one get any lanes? This is a page taken from NVIDIA’s books.
The second PCI Express x16 lane of traditional P35 and P965 boards comes from the southbridge. Since the southbridge only has six lanes to spare, usually four of them are routed to the second slot, leaving two for the Gigabit LAN and SATA RAID controller for the IDE. Also unlike the NVIDIA SPP and MCP arrangement, the Intel DMI interface is only 2GB/s bi-directional (1GB/s up and 1GB/s downstream) which leaves a huge bottleneck for the graphics card, this is until now.
Today we are reviewing the ASUS Blitz Formula P35 motherboard which gives a whole new setup for Crossfire users. How does it fair compared to our GIGABYTE P35-DQ6? Let’s have a look.
