The next significant physical change for the G450 comes in the memory sub system. The G400 uses a 128-bit memory bus connected to 16 or 32MB of SDR memory. With the G450, Matrox decided to use a 64-bit memory bus connected to 32MB of DDR memory. By narrowing the memory bus, Matrox does not have to run as many wires between memory and the G450 processor. This gives Matrox more leeway in board design and lets them use less layers in their PCB, which saves Matrox manufacturing costs. By using DDR memory, Matrox can do this without reducing memory bandwidth. Another advantage of a 64-bit memory bus is better memory granularity. With a 64-bit memory bus, the minimum amount of memory Matrox can use is half that of a card with a 128-bit memory bus. As memory module density increases to the gigabit range, this will turn into a major cost savings. At this time, we do not know whether the G450 will come with SDRAM or SGRAM. Matrox will most likely choose which kind of memory depending on pricing and availability.

Another improvement for the G450 is a faster secondary RAMDAC speed, increased to 200MHz or faster. This allows the secondary monitor port on the G450 to use a 1600x1200 display, up from 1280x1024 with the G400. So with one G450, a user can have 2056x1536x32bpp on their primary screen and 1600x1200x32bpp on their secondary screen. That comes to 5,078,016 pixels being pushed by a single video card. Not too shabby. That qualifies as a whole hell of a lot of spreadsheet space and, if performance of previous Matrox cards is a good indicator, the picture will be diamond sharp. The primary RAMDAC speed should remain at 360MHz, just like with the G400-Max.

Matrox has also integrated a TMDS into the G450 silicon and will be building a DVI digital monitor connector onto the board as well. With the G400, a $60 add-in card is needed for digital video out. At this point in time, Matrox marketing material says the TMDS is capable of running at 1280x1024x32bpp. However, we have been told that there is a strong possibility of the card being able to run at 1600x1200x32bpp. We hope the G450 will be able to do the higher resolution, otherwise the product will suffer from the same limitation as the GeForce2 GTS .