AGi UD858 DDR5 TURBOJET RGB (DDR5-6800 CL34) Review – Speed Demon

Unboxing & Walkaround

The package of the AGi UD858 contains nothing else but the memory modules secured in a plastic tray – nothing out of the ordinary. The modules are surrounded by two metal plates acting as heatsinks, with a strip of RGB on top (partially obscured from the side view).

The RGB lighting are considered decently bright, though in its out-of-the-box form we’ve observed the lighting from two modules have the tendency to drift off sync. This should be fixable via appropriate RGB software, though you won’t find one from this manufacturer in particular.

Specifications

AGi UD858 DDR5 TURBOJET RGB (DDR5-6800 CL34)

Full specifications available in product webpage and datasheet.

Model Number	AGI6JWG16UD858
Frequency	6800MT/s
Primary Timings	CL34-45-45-108
Voltage	1.4V
Capacity	16GB x2
Dimensions	133.35 x 37.0 x 7.7 mm

Test System

CPU	Intel Core i9-13900K
Cooling	Cooler Master MasterLiquid PL360 Flux 30th Anniversary Edition Cooler Master MasterGel Maker
Motherboard	ASUS ROG Maximus Z790 HERO
GPU	NVIDIA GeForce RTX 3080 Ti Founders Edition
Memory	AGi UD858 DDR5 TURBOJET RGB (DDR5-6800 CL34)
Storage	Samsung SSD 980 PRO 256GB (Boot) Kingston NV1 1TB
Power Supply	Cooler Master MWE Gold 1250 V2 Full Modular 1250W
Case	VECTOR Bench Case (Open-air chassis)
Operating System	Windows 11 Home 23H2

Overclocking

Starting with the baseline of 6800MT/s CL34-45-45-108 @ 1.4V, we measure a latency of 69.4 nanoseconds, with read, write, and copy bandwidth measured at 102.6 GB/s, 90.1 GB/s, and 93.8 GB/s respectively via the AIDA64 benchmark. A 30-minute AVX2-based memory stress test courtesy of OCCT has shown no errors in this configuration. With that, time to push the modules and see how far they go.

The next step involves nothing but a simple step-up in memory clock to 7200MT/s, leaving voltage and timings both untouched. Surprisingly, it’s perfectly stable in our 30-minute stability test, and with that we’ve netted ourselves a substantial boost in bandwidth and latency, measuring 108.4 GB/s read, 94.0 GB/s write, 98.2 GB/s copy, and a latency of 66.8 nanoseconds, making an instant 4-5% improvement in all metrics.

The next overclock certainly needs extra voltage to pull it off, so we increased them to 1.435V (the maximum this ROG motherboard would safely allow) and give the UD858 a shot at a neck-breaking speeds of 7600MT/s. We also give the modules active cooling for good measure, though it only managed to hold for 7 minutes before errors starts appearing.

After a bit of back and forth with the clocks, we narrowed it down to the highest stable overclock of 7467MT/s at the same CL34-45-45-108 timings, with 1.435V voltage pumped to the modules. Here, we get 111.8 GB/s read, 98.0 GB/s write, 102.1 GB/s copy, and a latency cut down to just 65.5 nanoseconds. These numbers account for nearly 9% of bandwidth improvements and -5.6% latency reduction.

We tried the alternate route of widening the timings to CL36-48-48-112 at 7800MT/s (which still shaves half a nanosecond’s worth of latency), but the memory is deemed not stable enough to complete the 30-minute run. Feeding it extra voltage beyond safe limits (say, 1.47V) may have a small chance of making it work, but safe voltage limits exists for a reason – so we settled at 7467MT/s instead.

Verdict

To round up this review, I have a good news and a bad news. Let’s start with the good news: the AGi UD858 DDR5 TURBOJET RGB is a solid performer when it comes to overclocking – if speed is what you’re looking for, this set of modules got plenty of it on tap. It’s not the flashiest modules you can get on the market today, but it gets the job done.

Now, here’s the bad news (for Malaysians in particular): you can’t buy one. At least, not now. This model is currently exclusively available in Taiwan (its home market), though in our conversations made with AGi back in Computex 2024, the company has stated its intention to expand into overseas markets, including Malaysia.

But what kind of price are we looking at, at least? It currently retails at NTD 5,899 (though significant discounts are ongoing at this writing in Taiwanese online storefronts), which converts to roughly RM836 for this 2x16GB set. That’s still a cheaper price tag compared to equivalents sold here in Malaysia, despite the currency disadvantage. If the price is maintained by the time it launches here, we could be looking at the cheapest set of RAM at this clock speed.

Special thanks to AGi Technology for providing this set of UD858 DDR5 TURBOJET RGB modules for this review.