R9 280x keeps crashing and recovering.

try msi afterbuner and turning your core clock speed and memory clock speed down a bit and adding a bit of extra power % to your graphics card. Sometimes they just need more power or lower clock speed than stock and it should work fine plenty of guides on youtube

Have you tried different drivers?

what driver version you're using right now?

Hey man. I was having the same issue for days when I got my card. I eventually had to rma it.

But before we do that, let's try some solutions. Uninstall your current drivers and go to the amd website and download the latest omega drivers. (Even if you already have them downloaded do this.) Something may have gotten messed up during the download. Install the drivers as administrator and see if that works.

The second thing is what are your temps? A lot of times on the r9 280x (depending on the version) one or both of the fans start spinning incorrectly, which causes overheating issues. Download a program like msi afterburner to monitor your temps and you can set your fan profile to manual and increase it to 100 percent. See if this is your problem.

However if the fans are spinning incorrectly or slowly you will need to rma the card.

Did you try the drivers procedure? Or did you just test the fans?

Try reseating the gpu on your motherboard and make sure all the wires are plugged in 100 percent.

Come on man. Give us some more info. You can't just say still the same after every answer. Tell us what you've tried, games played etc.

Under full load what are the temps reaching?

I'm repeating some things to make sure we're not overlooking anything. Did you try turning down your graphics settings? Drop the screen resolution from 1920 X 1080 to 1280 X 1024 run your game on 'high' or lower (just testing, don't worry). See if you stop lagging or warping or studder stepping. You got a powerful card but you my have a program running in the background. Sometimes it may be well crafted spyware or backdoor agents (malicious software) screwing your computer and using your internet. Viruses and down loaders are notorious for downloading and dragging in spyware to 'observe' how you use your computer and purchasing activity. They search for and grab your files, send your information across the internet and hose it up.
I would FIRST, run Run Windows Defender (or an anti-virus program) then an anti-spyware program. Sometimes they disguise themselves, clutter a computer or multiply adware. Maybe using MalwareBytes is a good idea. Once again, I'm trying to reduce the possibilities to a specific point so being informative helps.
I trust you're not running any other programs (legitimate) at the same time you're playing games. Like you don't have Adobe Photoshop or Quickbooks (database stuff) open the same time you're playing a game. Close that stuff if you are.
You may have to use a different port.. Sorry, I don't know how to access one so you'd have to ask someone who does.
Your network connections. Test, just using one modem, no router, no switch. Have a high speed connection, no less. Go get a speed test and check the connection. Ah, hum. It's Free.

pick one.

http://www.speakeasy.net/speedtest/

http://www.zdnet.com/broadband-speedtest/

http://speedtest.comcast.net/

Then finally, it may not be any of this but your internet provider. Your internet provider doesn't have good service in your area and your ping is bad. The connections in your area are flaky.. . or someone is tapping into your internet service. Go outside and trace your connections. Comcast (get this) sent some lazy bozo service guy to my neighbor 's house and hooked up his internet to mine. Yeah, the 5h!t that happens.
Sometimes restarting your computer clears bad internet connections because the connections to game server are re-routed through different internet servers along the pathway. It's possible it's your internet provider.
I trust you know how to reseat your computer's hardware. Like each item, ram, video card, wireless card, computer connections USB, RJ45, too. Unplug the external hard drive. It's not going to hurt anything so unplug it.
Sometimes the game itself needs to be repaired or updated. If it does, do so. Sometimes your opponents in the game have lousy computers or ping which is causing lag in the server. I crashed around other users and gamers who were using Pentiums and cheap laptops when I had an AMD HD7950. My Nvidia gtx 970 hates it, too. Not much you can do about that one. I know in BattleField 3 and 4, the admins kick users with high ping.
Take your card and plug it into a friend's computer or one you can use (not a library one). If does it's blackouts, send the card back. What I would do is call whomever you bought the card from and send it back. They'll give you an RMA number if it's still under warranty. And if you get a new one and the problem still exist, you know it's not the card.
There are times when a video card model or series is just bad. It happened last spring and summer with a batch of R9 280 and 290 and 'X' models. They were horrible. Crashing or not running at all. I only know a rumor: the clock settings on them were done for Bitcom users. You can still read the product reviews on NewEgg and Amazon for that period.
Always ground yourself when you're working on your computer. Don't just unplug it and lay the computer on the ground or carpet. Putting your hand on it won't make a bit of difference if you do that. Connect the computer to a grounding point. If your power supply has an off/on switch, turn it off but don't unplug it. You'll have ground but no power. Then depress the power button to remove any residual power in the computer for ten seconds. Using a grounding strap, wouldn't hurt.. Tell all of us everything that you done.

Update you BIOS.
Update your Driver to the Beta.
Check your power consumption.
Had this problem for about 5 months with a GTX 760 and I had to underclock it to get the error message to go away.
Hope the above will help.