Looking up the information on the board, I presume that you mean the MSI A58M-E35 because I do not find information on a board called the A58-E35. So, based on this, it does appear that board will accept the A8-5600K processor.
yes it will work but it will be a bit slower than in the original motherboard.
This is a microATX (mATX) motherboard that measures 9.6 inches on a side, which is the maximum size for a mATX board. The minimum size for this style of board is 6.75 inches on a side.
The form facter relates to the actual dimensions of the motherboard itself. There are 2 sizes: Large and Small. ATX = Large, mATX = Small.
The Asus P4SD can support up to four gigabytes of memory with its four memory slots.
Groucho matx
As it's a microATX form factor motherboard (compatible with ATX form factors as well) that's very likely to fit in your tower case. Some Dells are a tight fit, however, and while it may indeed fit getting everything put back together again could pose a bigger problem. Try searching for your specific model and "motherboard installation" or something similar to get a better idea if you can accomplish this.
ATX and mATX
its similar to an LPX motherboard .. but its smaller .. the LPX was designed to be slimline the ATX is designed to be mini ... i actually dont know im just guessing .. its a computer .. use it .. quit yapping
There are many differences between AT and ATX motherboards. The most noticable, without disassembly, are probably the keyboard connector (AT is much larger) and the power switch. The power switch for an AT motherboard clicks on and clicks off. The power for an ATX motherboard is a momentary push button that is always open unless pressed. Internally the best indicator is the power supply connector to the motherboard. An AT motherboard uses a two piece single row connector. An ATX motherboard connector is one piece with two rows of ten connections.
No, for the slim tower Dell Vostro 200, you will need a specified PATX psu. Only the mini tower can accommodate mATX-ATX psu's.
The main modern case form factors for consumer computer cases are ATX, mATX, and mITX. There are many others available, but the overwhelming majority purchased are one of those three.
Most DDR2 800, or better (e.g. DDR2 1066) should work, but to be sure that the RAM is compatible with the the motherboard, you can check the gigabyte webpage and download the PDF of compatible RAM- http://www.gigabyte.com.tw/Products/Motherboard/Products_Overview.aspx?ProductID=2314
If you want to have good air flow you need middle ATX or full. Cooler Master Half series is a good quality and will serve you well. Also Corsair makes good cases too.