I couldn't watch the game very carefully, but I thought that the Suns' effort was pretty good in the second half. The score was about even in both the third and fourth quarters.
The Suns held their own at forward and even at center, but simply got killed in the backcourt matchups. Aside from Joe Johnson, the Suns don't have any guards who are legitimate NBA players (at this stage in their careers). Barbosa, Jacobsen, and Eisley really should not be getting regular time on any NBA team right now; Jacobsen is probably the best of the bunch, but if he's not making contributions from behind the arc, he has little to offer. And they are are weak on both ends of the floor, not just on offense.
The experiment of starting Cabarkapa at SG was worth trying, I think, and even though it was a disaster tonight, it's probably worth trying again. But when the likes of Giricek, Lopez, and Bell completely outplay your guards, that means your guards really aren't good.