How We Keep a Ryzen 7600X Cool in the Jonsbo C6: IS-55 and Eco Mode

What cooler fits a Ryzen 7600X or 7700X in the Jonsbo C6, and how much speed 65 W Eco Mode really costs. Published benchmarks, charts and the exact setting.

A builder who runs both the ITX and micro-ATX versions of the Jonsbo C6 asked us a fair question: what CPU cooler keeps a Ryzen 7700X cool in a case this small?

Our short answer was the ID-Cooling IS-55. The longer answer is that the cooler is only half of it. The other half is power. Turn on AMD's 65 W Eco Mode and you give up a single-digit percentage of multi-core speed, and in games you mostly give up nothing.

This is the setup inside Raster Zero, which pairs a Ryzen 5 7600X with an IS-55 in a Jonsbo C6 and ships with 65 W Eco Mode turned on. Here is why it works and what the numbers say.

Start with what fits

The Jonsbo C6 is about 15.9 liters, roughly the footprint of a current console. Jonsbo lists a CPU cooler limit of 75 mm, so tower coolers are out.

The ID-Cooling IS-55 is 57 mm tall with a 120 mm slim fan (15 mm thick, 500 to 2,000 RPM, rated at 31.2 dBA). That leaves room above the fan to breathe.

The open Jonsbo C6 frame with the side and top panels removed, showing the power supply, graphics card and fans packed into the micro-ATX layout.
Everything in Raster Zero is a standard desktop part. The trade-off of a case this size is that the CPU cooler can't be taller than 75 mm.

A low-profile cooler can hold a stock 7600X, but at stock the chip will run up to its temperature limit and push the fans hard when it gets there. That is the noise people notice in a living room.

Why the X chips run hot

The 7600X and 7700X ship with a 105 W TDP. In practice that allows up to 142 W of package power (PPT), and the chips boost until they hit either that limit or their temperature limit. With a small cooler, temperature usually gets there first.

TechSpot showed this with AMD's small Wraith Spire box cooler: a stock 7600X hit 101 °C in Cinebench R23 and scored 5% lower than the same chip on a 360 mm liquid cooler. Switching on Eco Mode with the same box cooler brought the peak down by about 7 °C. (TechSpot, Oct 2022)

What Eco Mode actually changes

"65 W Eco Mode" sounds like a hard 65 W cap, but it isn't. AMD's 65 W setting sets the package power limit to 88 W, with current limits of 75 A (TDC) and 150 A (EDC), down from 142 W, 110 A and 170 A at stock. (PCWorld)

Even at stock, ASCII.jp saw a 7600X peak at 101.9 W, well under the 142 W allowance, so an 88 W limit only trims the top end. That top end is mostly all-core work like rendering and compiling.

How much performance you lose

ComputerBase tested both chips at four package power limits. In Cinebench R23 multi-core:

Single-core scores barely moved at any of those limits. (ComputerBase, Jan 2023)

Bar chart: Cinebench R23 multi-core as a percentage of stock. Ryzen 5 7600X 100% at 142 W and 88 W, 94.5% at 65 W, 82.4% at 45 W. Ryzen 7 7700X 100%, 96.4%, 88.5%, 74.2%.
Eco Mode's 65 W setting (88 W package power) cost the 7600X nothing in ComputerBase's Cinebench run and the 7700X under 4%. The losses only grow once you cap package power itself at 65 W or below.

The 7700X has two more cores to feed, so it feels a power cap sooner. In Eco Mode it still stays within single digits.

Bar chart comparing a stock Ryzen 5 7600X with Eco Mode: Cinebench R23 multi-core 15,149 vs 14,470, single-core 1,968 vs 1,962, Final Fantasy XIV 5,246 vs 5,253, peak package power 101.9 W vs 88.0 W, peak temperature 87.4 °C vs 80.0 °C.
Same 7600X, same test system. In Eco Mode the game score didn't drop, while peak power fell 14% and peak temperature fell 7.4 °C.

ASCII.jp measured the same pattern on a 7600X: 4.5% lower in Cinebench multi-core, the same single-core and Final Fantasy XIV scores, peak package power down from 101.9 W to 88 W and peak temperature down from 87.4 °C to 80 °C. (ASCII.jp, Jan 2023)

TechSpot found gaming results "basically identical" between stock and Eco Mode across the games it tried. (TechSpot)

How to turn it on

You can switch it on in two places:

  1. Ryzen Master (Windows): choose the Eco profile and apply it. This is AMD's one-click route.
  2. BIOS: most AM5 boards have an ECO Mode option under AMD Overclocking or Precision Boost Overdrive, where you pick the 65 W TDP setting. Menu names vary by board. Some boards only offer manual limits; there you enter 88 W PPT, 75 A TDC and 150 A EDC.

On SteamOS, use the BIOS route, since Ryzen Master is Windows-only. Note that the manual limits live in the PBO menu. AMD's Ryzen Master page warns that settings outside AMD's specifications can void your warranty. Eco Mode lowers the limits rather than raising them, but if you are unsure, check with your board maker.

After a reboot, run a game you know and a multi-core test. You should see lower peak temperature and package power, with frame rates in the same range.

What we do in Raster Zero

Every Raster Zero with a Ryzen 5 7600X ships with AMD's 65 W Eco Mode already enabled, so you don't need to change anything. It's the 65 W-class tuning goal from our SFF thermals guide, applied at the factory. A case the size of a console sits in a living room, so quieter fans matter more than the last few percent in Cinebench.

If you have a 7700X, the same setting works. Expect a slightly bigger multi-core loss than on the 7600X in all-core work, and the same story in games. If you want the lowest heat with no tuning at all, a 65 W chip like the Ryzen 5 7600 or the 7500X3D is the other route.

Configure & Buy Raster Zero

Common questions

What CPU cooler fits the Jonsbo C6?

Jonsbo lists a 75 mm limit for the C6. We use the 57 mm ID-Cooling IS-55, which leaves clearance above its 120 mm fan.

Does 65 W Eco Mode cap the CPU at 65 watts?

No. It sets the package power limit to 88 W. ComputerBase measured no Cinebench multi-core loss on a 7600X and 3.6% on a 7700X at that limit.

Does Eco Mode lower gaming performance?

Barely. TechSpot found results basically identical to stock, and ASCII.jp's Final Fantasy XIV score on a 7600X didn't drop.

Is a 7700X too hot for a small case?

Not with a sensible power limit. In Eco Mode it lost 3.6% of multi-core speed in ComputerBase's test. A harder 65 W package cap costs it 11.5%.

Sources

Last verified October 12, 2026.