I am going to hate figuring out what PC components are busted.
Oh, it's actually quite simple. Start with PSU, replace it with new one, see if it helps. If it doesn't - continue with motherboard. Then the cards
After that, just leave the working parts as a spare
Any recommendations on brands of multimeters I should get?
Oh, it doesn't have to be a Fluke - any decent budget brand like Mastech/Extech/Craftsman will do. Just make sure to get it from a good retailer, not from DealExtreme or eBay or whatever, so you can easily return it for replacement if it's defective.
Would a 1000VA rating UPS be enough for a 1250 Watt PSU?
Well, let's see, your PC has a couple of 780ti in SLI setup, so at full load it might go up to 700w of power consumption. Might be lower, but just to stay completely safe you should probably go for a 1500va/900w rated unit. As a bonus you'll get a pretty LCD screen on these units which can be useful for determining the power consumption of your PC. It will also have a network surge protector, which you should really use if you have wired network.
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