You'll need to get a card that IS on the VMware HCL...
Go with Intel brand cards (I've had better results with these over Broadcom cards).
ALL NIC's will need to be Gb, so no 10/100Mbps cards here.
Do a search on the HCL under the IO Devices tab for keyword "pro/1000"; type: Network; Manufacturer: Intel; Product Release Versions: select from 4.0 through 4.1... You'll get 41 results...
I'm using Intel 82546EB (dual port) and 82546GB (quad port) copper cards in my ESXi 4.1 how without any issues... Granted, these ARE server class cards, not desktop grade/class (there really is a difference)...
Search on Newegg for the "[PRO/1000 GT|http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&DEPA=0&Order=BESTMATCH&Description=PRO%2F1000GT&x=0&y=0]"... It's a ~$30 card (single port)... It's also on the HCL... That's about the cheapest adapter I'd be comfortable recommending to anyone... I would also say to buy this in brand new condition (still sealed in the box) NOT used... You have no idea what's happened to it if it's used...
VMware VCP4
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