Trouvé sur le web et pas vraiment tout compris :
""difference ... between the DWL-G650 and the DWL-G650+ ... isn't jumping out at me"
That's because of the wonderful D-Link naming / numbering conventions.
The key items to note are the G and the +
G means that it is an implementation of the IEEE 802.11g standard
+ means that it implements the 22 Mbit/s speed
Back before the 802.11g 54 Mbit/s standard was ratified, there were moves to provide higher speeds than the 11 Mbit/s specified by the 802.11b standard.
One wireless chipset manufacturer, Texas Instruments (TI) developed a new modulation technique, PBCC, which allowed speeds of 22 Mbit/s (and higher...)
D-Link and a number of other manufacturers incorporated the TI ACX100 chipset into their products, allowing them to achieve 22 Mbit/s, and refer to the products as "802.11b+". In fact they are non-standard. Examples of D-Link products which use this chipset include the DSL-604+, DWL-520+, DWL-650+
PBCC *is* allowed in the IEEE 802.11g standard as an 'option'. But few manufacturers (only TI?) implement this, so the number of 802.11g 54 Mbit/s devices which implement the intermediate 22 Mbit/s speed is limited.
D-Link has retained the + for newer 802.11g products which use a TI chipset and provide the optional PBCC encoding.
You are right in that the + is a later model (although there are multiple hardware revisions), but the key difference is in the wireless chipsets used.
So, the DWL-G650 is based on an Atheros chipset and does not implement 22 Mbit/s, while the DWL-G650+ is based on a TI chipset and does... Clear as mud?
It becomes even more complicated, because Atheros has implemented its own proprietary extensions to 802.11g which it calls "Super G". This relies on data compression and the use of two adjacent wireless channels to provide so-called 108 Mbit/s speed.
This technology is only compatible with routers based on the Atheros chipset. It does not work in ad-hoc mode. It does not work with routers based on other companies' products. It requires a router firmware upgrade and upgraded device drivers which all support 'Super G'. As all wireless channels overlap, there is reportedly greater interference with other nearby wireless LANs. So Atheros has made itself a little bit unpopular - except of course among users ejoying the higher speeds!
I believe the new DSL-G604T router is based on a TI wireless chipset (TNETW1130 ?). That means you won't be able to use the new driver functions of the DWL-G650. Both the DWL-G650 and DWL-G650+ should however run fine at 54 Mbit/s against the DSL-G604T.
Hope this helps"