Here in our installation, for our base station, I went from a WRT54G to a WHR-G54S to a WHR-HP-G54.
The Buffalos are on DD-WRT, the original Linksys v5 was stock FW. Although I failed to do thorough comparison testing, especially with the Linksys, I can make a few comments:
First I had the linksys v5 going there, but decided to go with the Buffalo WHR-G54S and DD-WRT. I sold the Linksys.
I was running the WHR-G54S on DD-WRT V23sp1 at 84mw transmit. All was well. Then I subbed in the WHR-HP-G54 on DD-WRTv23sp2 and started testing. Everything else, including the external antenna rig, remained the same, and I tested it on the same afternoon.
With the HP set at 28mw transmit, people noted that they were getting weaker signals than with the non-HP Buffalo at 84mw. One client with great reception went from 5 bars to 4, another marginal went from 2 bars to 1.
I cranked up the power on the HP to 84mw and everybody had the same signal strength showing on their clients.
Conclusion: 84 on the HP (with v23sp2) gives you about what 84 on the non-HP gives. The linksys I had at the base was weaker still, but it had stock firmware. Why is 84mw on the HP working like 84mw on the non-HP ? Well, after a thorough discussion on the DD-WRT forums.... nobody knows !
"Brainslayer" (the DD-WRT maestro) isn't talking. See:
or see topic: "Buffalo WHR-G54S vs WHR-HP-G54S"
Be sure to read all the way through as there are various different conclusions made along the way. The best takeaway I got from this thread is: use V23SP2 and go with 84-100 but it might be better to use SP1 and go with 10mw. They changed something from SP1 to SP2 but they're not telling. My guess is that they don't exactly know how the change affected output and are waiting for the users to sort it out.
I can add that the other day I cranked the HP up to 150 mw when I connected some distant clients. It barely improved (as expected) their received signal, but then, an hour later, when it was getting baked in the sun, it stopped working. (I forget the details, sorry) Upon inspection, it was hotter than usual. I cooled it off, rebooted and immediately knocked it back down to 84. Worked fine again. I don't know what really happened. I'm not trying higher power again ( over 100mw) on SP2.
I'm planning to put in sp1 sometime (at 10mw) and see how it works.
OK. On the RECEIVE side, the HP really shines and I can see a greatly increased signal quality and level as shown in the DD-WRT status. I'm basically getting 6-10 dB improvement on the receive end with the HP over the non-HP. Funny, but it seems that the HP is more a "rabbit" than an "alligator".
Somebody said the HP actually has a different Broadcom chip than the non HP - it's an "E" (for enhanced?)
Quote: "The BCM5352E also features Broadcom's new BroadRange technology, a standards-compliant hardware enhancement that extends the range of 54g- based wireless devices. The technology uses advanced signal processing techniques to provide the industry's best receive sensitivity, enabling Wi-Fi users to maintain high-speed wireless connections at up to 50% further from an access point.
BroadRange technology uses advanced digital signal processing techniques to provide the highest receive sensitivity of any 802.11g chipset on the market. "
Somebody else said: "The unit has actually 2 amps. There is one on the Tx line, and one on the Rx line. That is clearly visible on the schematics and photos found in the forum. The amplifier, that was affected by the boardflags was the Rx amp. And the amplifier affected by the 10mW setting is the Tx amp. (It even makes sense if you really think about it). The Tx amp is Anadigics AWL6153 "
All this came off the DD-WRT forum. I don't know if they are correct.
I now have another Linksys WRT-54G V2.2 running DD-WRT about 400 meters away from the Buffalo HP. It's working as a repeater in WDS. The linksys seems weaker on the receive side. Maybe on the transmit side too. Both are set at 84 mw transmit. On the Buffalo HP side, I see a 19% signal quality, or -78 signal. On the linksys side, DD-WRT reports -88 signal at 8% quality.
Now, one might assume that the Linksys has a stronger signal and that's why it shows stronger on the Buffalo HP, but based on all the other indications, I see it as another sign that the HP is 10 db more sensitive than the standard Broadcom device.
In sum, from my experience in the field here: Set the HP at 10mw with v23sp1 or 84mw with v23sp2. Don't expect more power than the regular, but expect much better sensitivity. Don't know why that is for me. Maybe 10mw with sp1 is better and I need to change versions !