Starting with your first question:
1)This cooler will not work with an old socket A (462) motherboard, this cooler is for later boards with sockets 754/939 or 940.
2) Is it any good? about average and about equal to the retail supplied fan that comes with Athlon64's
Should be good enough for low end X2's like the 3800/4200.
4) Bearing in mind budget then: Asus M2N-X, M2A-VM,
M2N4-SLI or M2A-VM HDMI depending on wether you want integrated graphics or not.
Abit: AN52, KN9S, AN-M2HD
3) If you want to keep your DDR ram then you will have to buy a slightly older socket 939 board and dual core 939 CPU, the best boards are based on the Nvidia Nforce4X/Ultra or SLI chipset.
This Foxconn board is still on sale and is very good value for an SLI capable mainboard plus you get to keep your memory. Obviously not the latest technology but feature packed for the price.
So in short: if you want to keep your DDR memory then you will have to go Socket 939 mainboard and CPU.
AM2 (940) is newer but will require DDRII memory
Martin
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