If I had to guess, it's Broadcom. While their merchant switching ASICs (Trident+, Trident2) have become good enough to displace most custom spun ASICs for 10 Gbps and 40 Gbps switching, their NIC hardware has long been somewhat of a disaster. Interesting to note is that Broadcom has basically sold the NIC business to QLogic: http://www.broadcom.com/press/release.php?id=s832628
