Lenovo currently offers four form factors of desktop computers – each with their advantages and disadvantages. The pictures that you’ll see here are not the latest, but they’re the best hires pictures i could find – current models no longer have floppy drives, but the cases have remained the same size and design.

The classic mini tower

The mini tower is found in almost every company. They usually offer place for a second hard disc, a second optical drive, a fully fledged PCI-E x16 graphic card (not all models), and a few more expansion slots (usually PCI-E x1 and two PCI slots). As such, much office furniture has been made to be fit with mini tower PCs, and this is why they still see much use.

Mini towers are a great choice if you might want to expand the use of the machine, by adding specialized equipment to it. Some models offer more DIMM slots (4 instead of 2), which allows easier upgrade of system memory.

In my opinion, mini towers are oversized for most office workplaces. They eat much space, cabling them is more difficult as the standard cables on equipment get shorter and shorter, and they do not always offer advantages for a plain office worker.

However, Lenovo recently started shipping ThinkCentre towers with 2GB of standard memory if ordered with Windows Vista. This has not yet become a reality for the other form factors, which puts the cost advantage at the ThinkCentre towers.

The small form factor (SFF) PCs

The SFF PCs are the size i think is ideal for most purposes. They usually offer place for two DIMM slots, a standard sized optical drive, and two expansion slots (usually an Intel ADD2 slot (for DVI) and a single PCI-E x1 or PCI slot).

They are big enough to still have room for expansion, are pretty quiet since the diameter of the fan can be large enough, and offer the advantages of a PC that can be installed right on the desk. The main reason for this is usually reducing the hassle with cabling various devices, using USB hubs, USB extender cables and other gizmos.

A speciality of Lenovo’s SFF product line is that they ship with a stand that allows them to be set next to the monitor, not below it. This is an advantage for people with big screens or that want to look down to their screen.

The biggest disadvantage of the SFF models is that you can only fit two DIMMs into it. When ordering low volume, you currently get models with 2x512M pre-installed, and upgrading to 2x1G (that are IMO required for Vista) adds an unnecessary cost. Lenovo will probably start offering models with 2GB by default soon, so this point will no longer be that important.

The ultra small form factor (USFF) PCs

Until recently, the USFF models were the smallest PCs you could buy. They are built using desktop CPU and mainboards, but use some laptop components like the optical drive. The biggest problem of these little machines is heat – while the cooling is nice and quite during normal office work, it could get extremely noisy when you were loading the CPU during extended time periods (especially the PIV/PD models had big problems with that). Now that these models use Intels Core 2 CPUs, the problem is no longer that big, but still existent.

Not all USFF models offer expansion slots, and the laptop optical drive offers additional disadvantages when looking for non-OEM replacements a few years down the road. Again, the earlier comment about only being able to fit two DIMMs into the machine applies.

Honestly, i’ve never seen much of an advantage of this form factor over the SFF models, maybe someone can enlighten me.

The A61e

Lenovo recently introduced the ThinkCentre A61e. I’m sorry i didn’t find a better shot of this machine, but they’re not shipping in Switzerland yet. This machine is smaller than the USFF models, and maybe it will get a new designation (like nano form factor or something equally silly – i hope not).

The biggest change from all the other product lines is that this machine has moved to an external power supply, and switched back to a normal optical drive. I really dislike external power supplies, because they can get lost, can be expensive to replace, etc.

Again, i’ve never seen this machine or made practical experiences with it. I didn’t see the need for USFF models, and i certainly don’t see them for this little baby. It looks nice though, and it might be a very good choice in a different field of operations.

If you can’t use 4GB of RAM, and have PAE enabled, you have bought hardware that doesn’t support 4GB of RAM. There’s a KB entry, which details some of the problems. If you want to use the full 4GB, buy better hardware.

Lenovo sells almost all ThinkCentre models as SFF and as USFF. USFF uses Laptop CD drives. Not a bad thing, i think. They’re much easier to place than full PCs. And you usually don’t have any expansion cards in Office PCs anyway. Newer SFF/USFF models even come legacy free (No PS/2, some of them have IEEE1284, though).

I’ve never experienced higher failure rates with them either. Just in case you’ve never seen one of them before, here’s a nice picture: Lenovo’s IBM branded SFF ThinkCentre.

Oh, and the big reason for selling them? They’re cute!

In case you’re laughing now, that’s what a customer told me why he bought them. And he was serious.