Ok the Corsair h110i Rgb pro
but according to the compatibility list on amazon and the official evga page if it works with tr4 (Intel LGA2066 2011 2011-v3 1200 1150 1151 1155 1156 1366, AMD AM2 AM3 AM4 FM1 FM2 TR4) and the h110i rgb pro costs 130$ and the evga 85$ :v
If EVGA says that this product is compatible with the TR4 mount, I'm inclined to believe them.
That said, there's a reason why this AIO is cheap: the cooling performance isn't particularly stellar.
The cooling block is an older Asetek design with a bayonet mount and a small round copper cooling plate. I'm not sure if it will provide adequate coverage for TR4 CPUs to provide satisfactory cooling.
I currently have this AIO on my Ryzen 7 3700X (65W TDP) which maxes out at 82 °C during a Cinebench R23 benchmark (about 120 W PPT with PBO enabled).
The original reason I bought the EVGA CLC 240 AIO (non-RGB version) was to cool an RTX 2070 Super Founders Edition graphics card with the NZXT Kraken G2 bracket. While the GPU produced more heat than the 3700X, the TU104-410 GPU chip itself is smaller (die size about 24mm x 24mm) so the AIO's small cooling plate provided enough coverage.
This product's cooling block is intended to be connected via included USB cable to an internal motherboard USB header. There's EVGA Flow Control software to be installed which controls the fan speed and provides a readout of the pump speed and coolant temperature. The coolant pump is bipolar so third-party monitoring utilities like HWiNFO only show half the pump speed. If HWiNFO says 1500 rpm, the motor is actually running at 3000 rpm. The EVGA Flow Control software displays the correct speed.
However I am using different fans (Noctua NF-P12 redux-1700 PWM) than the EVGA originals.
I installed this AIO so the two Noctua fans are controlled by the primary CPU_FAN fan header; the AIO pump is on the AIO fan header. The motherboard UEFI does the speed control for both; I did not set up any fan curves in the EVGA software and disabled it from starting when Windows boots. The UEFI fan curves are set to max at around 1400 rpm (about 75%). I might get lower temperatures if I ran the fans faster but I don't push the CPU to its limit very frequently on this build (I definitely favor quieter acoustics). The 3-pin AIO pump runs around 50% speed (6V DC) while the CPU is idle and will run at full speed at its peak (12V DC).
I wouldn't expect this AIO to properly cool a Threadripper even if the mounting bracket is physically compatible with the TR4 platform.