my motherboard is an asus m4a87td evo, and I'm wondering if it can use the new AMD FX 8-Core Black Edition. I read what cpus it supports but I'm not sure since it's a newer cpu. I'm still learning the basics of pc building so I'd appreciate any feedback.
I'd give it another 2-3months and keep looking at BIOS-CPU updates. Better to stall a few months and see if you can get what you want without paying a premium than to pay that exta $ and then see three months later that you'd have been okay. In the meantime, save your pennies and you'll end up winning either way as prices drop. That being said, there's a limit to how long to play the waiting game. I usually base my builds on a socket roadmap and current finances. I've got a 7yr old AM2+ build that's still going strong and am speccing an FM2 ITX-VESA build with a few scrounged notebook parts. Intel is typically the more powerful performer but AMD usually delivers more bang for the buck if you're looking at the overall longevity of the platform.
*Question - What is the main use for your rig and what's the current CPU?
Beyond that, if your main focus is gaming then I'm going to question what your vid card is. Most games are GPU bound and even those that are CPU bound will work fine off of the CPU you listed (Phenom II 945). You may want to look into a new video card in order to boost you FPS. What's your current vid card and what's your current PSU?
Without a new motherboard your best options are Phenom II X4 955-980 or Phenom II X6 1075-1100. If you can find the Phenom II X4 960T thats a good chip too and you have a good chance of unlocking cores.