Good RAM for Vista is even more important and Vista does push it a bit harder.
I've even had headaches with "good" RAM. I'm running two nearly identical PCs.... one with Patriot 4-4-4-12 and one with Corsair 4-4-4-12.
For Patriot I'm on my 3rd replacement set for two of the sticks... and the 3rd set didn't work correctly until a BIOS update... right now that one is finally (crosses fingers) rock solid. The Patriot RAM caused the "display driver
stopped responding" error for my PC... ran good for about 3 weeks... then the error happend more and more. I thought it was either bad driver or maybe a bad graphics card... but then one day I found my PC had crashed to a BSOD and on restart the PC wouldn't even boot to BIOS, just a beep code. After some swaping of RAM sticks I found the problem.
For the Corsair... it was rock solid and never had any problems with Vista 32-bit.... even after going to the 4GB mark, no problems (minus the 32-bit limit).... but when I changed to Vista 64-bit, it took a patch provided my MS (and linked by a nice user here) to get my PC running again. Also, I should note, that the "display driver" error.... gone.
Moral of the story....
I usually only buy Corsair because I've never had any real problems with it. Due to a trusted site (sharkyextreme.com) I went with Patriot due to one of their guides.... I will never buy Patriot again. Corsair still works great and the problem I had is more an issue with Vista and certain hardware configs vs a problem with the ram itself.