so I just built an x299 computer using the core i7 7740x CPU. my temps are all over the place I just put thermal grizzly on CPU and still temps all over the place. any way to make this cooler? I have the EVGA CLC 240mm cooler should I go the next size up?

I did overclock followed the instructions for x299 overclocking. I was at 5ghz I was hitting very close to 100c. then I went back to the normal clocks but the board fluctuates a lot. it can go from 38c to 50c at a blink at an eye no overclock at idle. right now it goes from 38 to 39 then 40c.

Make sure the mobo BIOS is up to date with the latest.
 
See the OC Guide for EVGA X299 DARK motherboard if you haven't yet.

Vcore under load is what matters most..Try getting that down as low as is stable under load..When overclocking, I would use 'Adaptive' CPU voltage because that only applies extra Vcore when the CPU is running at Turbo frequencies.
 
Enabling/Disabling Vdroop will affect CPU Vcore in a big way under load..Default is Enabled..Disabled will cause the Vcore to increase under load.

You can set Windows Power Options to 'Power saver' in Control Panel -> Power Options.

You can delid the CPU and use Thermal Grizzly Conductonaut between the IHS and the CPU die  instead of the less-than-impressive Dow Corning stuff Intel uses, and also between the cooler and IHS (that lowered my cores temps by a whopping 20C)..Careful, because it's liquid metal..Kryonaut Extreme would be a great conventional TIM.

Those temps with no overclock are OK.

Hi also maybe in future look at something a little stronger then a 240mm AIO cooler. Thats now if you are willing to go that route. Just know once you go down the watercooling rabbit hole you will find it hard to get out!

Direct die?

yeah i am going to get a 280 soon in a couple of months or so