Some buying questions

[Smalltalk80]

I appreciate answers to any of these questions. Thanks!

Does a 7200rpm drive give off much more heat than a 5400rpm one?

Which wirless card is better (they cost same)?
Intel PRO/Wireless 3945ABG (US/CAN/LA/AP)
ThinkPad 11a/b/g Wi-Fi wireless LAN Mini-PCIe US/EMEA/LA/ANZ

Are T40 and T60's Combo/DVD-ROM drives exchangeable?

It costs $170 to upgrade memory from 1G to 2G, while at the same time the website sells 1G memory at $156. What is lenovo thinking?

Finally, is there sales tax in Illinois?

[tomh009]

The 7200 rpm heat difference is relatively small (less than 1W over a 5400 rpm drive) and most readers here consider that a small price to pay for the additional performance.

Again, the consensus on these forums is that the Atheros-based ("ThinkPad"-branded) wireless cards are preferable to the Intel ones.

T4 series and T6 series both use Ultrabay Slim.

I can't say much about memory pricing or Illinois sales tax though ...