<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><DIV><BLOCKQUOTE type="cite"></BLOCKQUOTE></DIV>It should work. Last year I upgraded my Quicksilver from a 733MHz to a Sonnet 1.4GHz, granted I was already running Tiger. To play it safe, back up your data files, then upgrade the OS. If it does work, try a fresh install of Tiger with the new processor. I don't know about your processor, but with the Sonnet there is a small patch that had to be applied after the OS install so that the OS sees the processor properly, in other words, it'd see the ram & cache but wouldn't report the processor w/o this patch.<DIV><BR><DIV> <SPAN class="Apple-style-span" style="border-collapse: separate; border-spacing: 0px 0px; color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; text-align: auto; -khtml-text-decorations-in-effect: none; text-indent: 0px; -apple-text-size-adjust: auto; text-transform: none; orphans: 2; white-space: normal; widows: 2; word-spacing: 0px; "><DIV>Patrick J. Runcie</DIV><DIV><A href="mailto:macandlinuxuser@gmail.com">macandlinuxuser@gmail.com</A></DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR class="Apple-interchange-newline"></SPAN> </DIV><BR></DIV></BODY></HTML>