Zirkov

I doubt that will work, possibly you may not get a video signal since the card is expecting 3 8pin pcie power connectors to be plugged in. But if you do try only 2, you won't damage your gpu. Also playing at 1080p will not likely cause your video card to use less power, if anything your system will draw more power since at lower resolutions your cpu will be at higher utilization unless you limit the frame rate in games so that your video card does not go to 100% load. There is no guarantee if do all that you have suggested doing will get the 7900 xtx Nitro+ to work with your current psu while gaming, but you can have fun trying :). But at the end of the day you may need to get new power supply anyways and given my own personal experience with the 7900 xtx Nitro+ I would recommend started at 1000w for a psu, preferably using the new ATX 3.0 standard. Of course the other option is to pick a less power hungry gpu.

@Marcii I just bought the same 7900 xtx and had a Seasonic Prime 850w titanium power supply and my computer was shutting down due to over current protection circuit cutting in (likely from transient power spikes from the GPU). The Nitro+ was drawing just over 400w (as reported by AMD adrenalin) when gaming at stock. I did use the automatic under volting feature in the adrenalin software and that reduced power draw to just under 350w. Was good for a week before it I got another shutdown. After getting another couple of shutdowns over the next two days I just went out and got a new power supply last weekend. I went total overkill with the new psu, got another Seasonic, one of thier new Vertex GX models at 1200w (and here I thought my 850w was overkill when I bought it over 6 years ago... lol) that support the new ATX 3.0 standard. Since installing the new psu, I haven't had any issues and I turned off the under volting and switched the bios back to it's OC mode. I supposed I could have tinkered with power settings to reduce power draw even more but I would rather cranked it up to 11 and pull more power than turn things down, but that's just me. On Sapphire's website they recommend 800w minimum power supply for the 7900 xtx nitro+. But my 850w psu didn't work for me. In my case (pun intended), I have 4x140 fans, 2x180 fans, plus the 2 fans on the noctua DH15, that I'm currently using, plus rgb lighting with my 5800x and 32GB (2x16) of 3600 ram (with rgb of course) and two nvme SSDs (and that's not mentioning any peripherals I have plugged into the computer, all of which is drawing power as well). Not sure if you will have success with tuning down the power on your soon to be new nitro+ with your current 700w power supply but would be fun experiment to try . And don't forget that every fan, rgb light strip, ram stick, etc will all draw power. When I installed my new gpu, I also put in two more sticks of ram and pulling them out afterword reduced how often I was getting shutdowns when gaming. So I was on the knives edge for power, so why I went with the aforementioned psu. My recommendation would be to consider a 1000w or greater power supply, preferably using the new ATX 3.0 standard. Though I suppose 850w psu using the new standard could work too since it would allow for transient spikes of double the power draw (which would be 1700w on a 850w psu). That just my thoughts

@Prizzo I will concur with @Spotty, that is the sound of hard drive operating normally.

RMA'ing the gpu would be your next thing to do. I doubt it's the drivers or os since you already tried a fresh install of windows 10. Switching to windows 7 likely won't help if there is something wrong with the graphics card itself. Only other thing to do to be 100% certain is to put the graphics card in another computer to confirm it's the gpu. Other wise just RMA it.

Possibly the motherboard, but before you go and replace that, try getting your hands on another graphics card if you can and put that in your system. Make sure you do a clean install of the drivers after using DDU. If the crashes are resolved, then you know it's a bad graphics card, otherwise could be your motherboard. Only other thing it could be is some weird software/driver conflict. P.S. If you have a local computer store, you can buy a graphics card from them and return afterwards if it's not the problem. I did that with my mom's computer, only it's was a motherboard that I bought and returned. Had a bad FX 6300 that I RMA'd back to AMD. EDIT: Thinking a little bit more on your issue, easiest way to test if it's your graphics card or not, is to test your system with no graphics card installed. Remove the gpu and remove the drivers for it using DDU, then plug in your monitor into your mother board(your board has a hdmi port on the back). Then run your computer with the integrated graphics of your 8700k and see what happens. Don't expect to play any games with decent fps (be more like a slide show ) but if you get no more crashes doing anything else, like browsing, watching youtube/twitch, then it's very good bet it's the graphics card. But if the crashes persist, then it's something else like motherboard or software like I suggest above.

@jjsyue Your issue sound similar to the problems I had when trying to push my old x58 system with an i7 920 to 4.0Ghz couple years ago. Only in my case I was using Prime95 to test stability with no issues but when I went to play BF4, it would crash and sound would go crazy. So it seems that maybe your system is not fully stable. Try putting your cpu and gpu back to stock and see if GTAV and BF1 crash or not. If they crash, you know it's likely not the over clock, but if both games run fine, then you need to play with your over clocks to make them stable.

@Norine looks like from your pictures that you didn't have good mounting pressure to the one side where you see the pre applied thermal paste is not disturbed (as I've marked in red below), i.e. not smudged. Try remounting the water block again and for good measure you can also reapply new thermal paste. Hope this helps and good luck.

From what you are describing and looking at your set-up, it seems there is no water flowing through your bottom rad. Only way I can think that is happening is that the water is finding a way directly from the inlet to the outlet, indicating there is a hole/incomplete seal between the two, possibly from a manufacturing defect that is finally causing an issue now. If you have another radiator, replace the bottom rad to see if the issue persists.

Actually, National Geographic as been a magazine since 1888 (source). The cable channel has been only around since 2001 (source).

Here's a over clocking guide I used back when I first got my i7 920: http://www.xbitlabs.com/articles/cpu/display/core-i7-920-overclocking.html. I'm still using my i7 920 and currently running it at 3.9Ghz (did have it at 4.0Ghz, but back it down due to stability). So you can over clock your i7-920, just make sure to get a good aftermarket cooler. Something you can do while you wait to make a decision on what new hardware to buy.