Hardware Test: PS3 Slim

The photography also shows that while the new motherboard is obviously smaller, it isn't actually that much smaller than the current fat PS3's mainboard. However, the difference is that the daughter boards that slotted in are now a thing of the past. Similar to the Xbox 360, everything is now integrated onto one board, cutting costs but not functionality.

So, let's hook up the beast and see what we can see.

What is interesting is that PS3 Slim comes supplied with firmware 2.76, which became officially available on 14th May of this year. Its successor, firmware 2.80, materialised on 23rd June. This suggests that Sony is right to say that there'll be no problem with availability of the new SKU - the firm has been producing the new model for months now, which presumably helps explain the many and varied leaks we saw of the new form factor.

So, onto some specifics. The PS3 Slim has a few more changes from the original "Fat" version of a more internal nature, some of which are discussed elsewhere on Digital Foundry. OtherOS support for Linux has gone the way of the Dodo, while top-end bitstreaming of advanced Blu-ray HD audio formats (Dolby Digital TrueHD and DTS MA Master) has been added, along with a bi-directional HDMI port. The bitstreaming function is all about pumping out the raw audio data of the highest-end sound formats to a dedicated audio receiver, which can (in theory) produce a better quality sound than the PS3's own decoder.

The bi-directional HDMI port manifests in PS3 Slim's ability to interface with a selected range of Sony's own Bravia HDTVs. The link is all taken care of via a conventional HDMI cable, and it allows you to use the display's remote to scan through the XMB. The screen also powers down an idle PS3 if it is put on standby, but in theory shouldn't interfere if the console is busy downloading or in a paused state in-game.

Both of these features have not been retrofitted to the older PS3 in the latest firmware update, so all the evidence points to the Slim clearly having a more advanced HDMI port - it will be interesting to see how Sony chooses to use it in the future. BraviaLink is, I would assume, just one use for the bi-directional interface and it could be deployed in other fashions with future displays or receivers. However, according to Japanese interviews with Sony, the new Panasonic HDMI controller is not an HDMI 1.4 chip, so there'll be no support for 3D Blu-rays or networking. However, there is nothing to stop Sony fitting a newer chip in a future model that does support these things and keeps PS3 at the top of its game as the best value, premium-level Blu-ray player.

Sony is on the record as saying that the PS3 Slim is 32 per cent smaller, 36 per cent lighter and 34 per cent more power efficient. It's the last figure that is of most interest to me as historically, the PlayStation 3 is a very power-hungry machine. During testing I managed to clock an NTSC launch unit draining a peak of 209 watts from the mains (max fans plus Killzone 2 = big electricity bill). Subsequent revisions of the PS3 hardware have resulted in much more environmentally friendly - and indeed wallet-friendly - machines.

While I don't have a 40GB unit on-hand for testing, the 135 watts mooted on online sounds about right for a unit that has seen the both the RSX GPU and the Cell processor shrink from 90nm down to 65nm. And indeed, it also tallies quite nicely with my measurement of a PS3 Slim running at full pelt in the same Killzone 2 test: a maximum of 101 watts.

The power savings are essentially possible thanks to a further die-shrink in the fabrication process of the Cell CPU - it's now at 45nm, similar to the latest Intel and AMD CPUs. Less power means less heat, and thus more reliability. The RSX GPU still remains at 65nm though, so I would suspect that it too will be replaced by a 45nm part sometime in 2010 for an even more power-efficient console within the same Slim form factor.

But enough small talk: let's get testing. The PS3 Slim is put up against the launch unit in multiple scenarios, while basic measurements were also taken from a first-edition Xbox 360 Jasper for direct like-for-like comparison against PS3 Slim's nearest rival. To really stress out the hardware into sucking out as much leccy as possible, the tests took place in a room with an ambient temperature of 30 degrees Celsius (which was fun to be in all day) and measurements were taken after all the installation, loading and gameplay tests had been done, just to make sure those cooling fans were running at top speed.

The Blu-ray test was on a MPEG2 disc by the way, I would assume that an h264-encoded disc will draw much more power. As it is, it seems that running an older BD is more power-efficient than leaving the XMB to idle.

The conclusion is remarkably obvious. PS3 Slim meets all the claims made by Sony for its efficiency and it is a remarkably "green" unit, edging out the Jasper edition of the Xbox 360 by a few watts during gameplay and having a significant lead in front-end idling and also in terms of the power draw in standby mode. Assuming that your environment is cooler than 30 degrees Celsius, it's fair to say that the PS3 Slim will turn out to be even more economical in "real life". The real eye-opener here is just how power-hungry the launch PS3 is. At full tilt, it is drawing more power than the theoretical maximum of the launch 360's power supply.

We've talked about the YLOD issue recently, and the bottom line is that regardless of the scale of the problem up against the competition, it is an issue gamers need to be aware of, especially for owners of the original units whose Sony warranties have long since expired. Assuming it is indeed a cumulative damage issue caused by heat as the evidence suggests, there is a very real argument in favour of chopping in your launch unit in favour of the new Slim - assuming you have no need for backwards compatibility with PS2 titles, of course. One thing that was obvious after the testing session was that the launch model was very hot to the touch, whereas the Slim was significantly cooler.

Not only that, but the Slim is quieter too. In the 30-degree heat of the test environment, the older unit soon spun up to maximum volume and while the Slim was clearly audible, it was nowhere near the level of the older unit.

In terms of how these cooler chips and greater efficiencies stack up with regards your electricity bill, it works out like this. 1 kWh (kilowatt hour) is called "one unit" by your utilities supplier. A good price for one unit of power in the UK is around 13p. Assuming a conservative 15 hours of gaming a week with the unit running at max power, a PS3 Slim costs £10.34 a year to run. The old PS3 "Fat" on the other hand impacts your wallet to the tune of £21.19.

Hardly an earth-shattering saving - less than a quid a month - but valuable nonetheless, and it's safe to say that those savings will multiply significantly for the most hardcore who laugh in the face of the concept of using their consoles for a mere 15 hours per week.