When Intel introduced its new LGA775 processor socket for the Prescott Pentium 4, it handed its customers a bigger dilemma than usual; should they upgrade their Socket 478 PC with a faster processor that was at the end of one particular road, or should they buy a new Socket 775 motherboard and processor to start at the beginning of a whole new upgrade cycle?

This is the same choice that we've faced many times over the years, but this time Intel raised the stakes with its 915P and 925X chipsets for the Prescott processor. The 915P supports both DDR and DDR2 memory, while 925X only supports DDR2 memory, but both chipsets only support PCI-Express graphics and not AGP. That's right; if you buy a Prescott processor and motherboard, you also have to buy a new graphics card and possibly new memory too.

Enter stage right ECS with its 915P-A motherboard, which uses the 915P chipset. It has both AGP and PCI-Express graphics slots, as well as a pair of DDR memory slots and a pair of DDR2 memory slots.

Of course you can only use one type of graphics card and one type of memory at a time, but the ECS board allows you to upgrade your motherboard and processor to move to the LGA775 form while retaining your old graphics card and memory. Then, at a later date, you can upgrade your memory and graphics as funds permit. You can see why ECS calls the 915P-A a transition product.

The 915P-A uses the ICH6 Southbridge without RAID, so you can connect up to four SATA hard drives, but you can't connect them together in an array. There's only one ATA100 connector, which is quite usual with current Intel motherboards.

The expansion slots are like nothing you have ever seen. You get a PCI-Express 16x, two PCI Express 1x, an AGP 8x and two PCI, and ECS includes all of the integrated features that you would expect in a modern motherboard. There's Gigabit LAN, eight channel Azalia audio with a CMI 9880 codec, four USB 2.0 ports and the usual legacy ports.

Unfortunately ECS doesn't provide any brackets to take advantage of the extra USB and SPDIF headers that it includes, and these days we consider that four USB ports are not really adequate.

The power connector is a 24-pin EATX unit, rather than the regular 20-pin ATX, although you can connect up a regular power supply; however, ECS warns that the Prescott process is a power-hungry piece of silicon.

The layout is very tidy, and the 915P-A is a very clever motherboard, albeit with a couple of provisos. The memory configuration prevents the use of dual channel memory, and we don't see the point of supplying four SATA connectors without also providing a RAID controller, but the real issue is performance.

We tested the 915P-A with a 3.6GHz Prescott Pentium 4 and it performed slower than a 3.2GHz Northwood Pentium 4 on an 875P motherboard. That means you have to install a faster processor to achieve a given level of performance than you might otherwise choose, and that carries a cost of about £150; that's a high price to pay to hang on to your legacy components.

The ECS 915P-A is a clever motherboard that allows you to upgrade to the new Pentium 4 LGA775 processor form, while offering you the choice of AGP or PCI-Express graphics, and DDR or DDR2 memory. The problem is that this choice carries a heavy performance overhead, making us unsure if it is worth moving away from the Socket 478 Pentium 4 in the first place.