Build your own laptop

Posted at: Tuesday 1st August 2006 by James Morris

James Morris shows you how to custom-build your own performance laptop without spending a fortune

AMD has also just announced the dual-core X2 Turion, which, unfortunately, isn't pin-compatible with previous Turions. It uses the new DDR2 memory controller, but on a 638-pin Socket S1, rather than the 940-pin Socket AM2. Four Turion 64 X2s have been announced - the TL-50, TL-52, TL-56 and TL-60. The TL-50 runs at 1.6GHz with two lots of 256KB Level 2 cache, and the TL-52 uses the same frequency but has double the cache. The TL-56 increases the clock speed to 1.8GHz, and the TL-60 to 2GHz. As these are 'L' parts, they all have a TDP in excess of 30W, with the TL-60 specified at 35W. You'll find it hard to track down a compatible chassis though. MSI recently announced its MS-1058 with Socket S1, but this only uses a 12.1in TFT, so it's hardly for power users.

Your choice of memory will also be dictated by your chosen platform. Unless you're lucky enough to get hold of a new Socket S1 laptop, AMD systems will use PC3200 DDR, and as the memory controller is single-channel, you're better off choosing a single module to start off with, so that you can use the second slot (if available) for future upgrades, unless, of course, you're putting the maximum amount of memory possible in to begin with. Intel laptops will either support DDR or DDR2. The 855 chipset only supports DDR while most versions of 915 support both types, but 945 is DDR2-only. Make sure you consult the specifications of your chosen chassis so that you get the right type of RAM. Also bear in mind that laptops use smaller SODIMM modules, so the RAM you'd buy for your desktop won't fit.

The MXM controversy

Back in 2004, laptop graphics appeared to be on the verge of a revolution that was particularly interesting to the hardware enthusiast. This is when Nvidia excitedly announced that portable graphics were being standardised under a new three-letter acronym called MXM, which stands for Mobile PCI Express Module. Instead of being hardwired to the laptop motherboard, or attached via a proprietary connector, graphics chips would be connected using a standard slot.

Many people excitedly thought that upgradable laptop graphics were at last a reality, but this still isn't true two years later. MXM is a standard, but only for the connection between the module and the laptop motherboard. Otherwise, designs vary widely, with different-sized PCBs. Some laptops even have the VBIOS on the motherboard itself, making it near impossible to swap graphics cards. Plus, even when this isn't the case, laptop cooling is still proprietary for the chassis in question, so a heatpipe that's adequate for a GeForce Go 6600 probably won't suffice for a GeForce Go 7900 GTX.

So, in reality, MXM is more for manufacturers than for self-builders. It allows them to keep their models up to date with the latest options without a total redesign - for example, offering a GeForce Go 7900 GTX instead of a 7800 GTX. And, since it's virtually impossible to buy standalone MXM graphics, upgrading is a moot point anyway. That said, MXM is the first step towards upgradable laptop graphics, and you can keep track of developments by heading to www.mxm-upgrade.com