Wireless signal stronger when running Windows

[scott8035]

Greetings. I recently converted my laptop from Windows XP to Ubuntu 9.04. When running under XP, my wireless signal strength (from a fixed location) was always 5 bars; under Ubuntu it's 2 bars. The wireless card is using the Ath5k driver; it's in a Toshiba Satellite U305 laptop. Dmesg says it found an Atheros 2425 chip. Is there some setting I can change that would affect the signal strength receptivity?
---scott

[leandromartinez98]

Do the performance differ? If not, it may be only the graphical indicator using a different scale for putting different number of bars for the same signals.