AMD Ryzen 9 7900 Desktop Processor Review

AMD recently announced new 65W additions to their Ryzen 7000 family of processors during their CES 2023 keynote. The three new SKUs launched consist of the Ryzen 9 7900, Ryzen 7 7700 and the Ryzen 5 7600. The addition comes about 3 months after the initial launch and ties into the launch of the more economical chipsets which also made their way into the market recently. Building an AM5 PC was comparatively more expensive since the choice was limited to the X670 variants and the boards based on those top-end chipsets were all expensive. Now, that’s no longer the case and we’ve got cheaper CPUs as well as cheaper motherboards. Considering that the new Zen 4 processors are built on the TSMC 5nm process, we will now get to see how efficient the architecture is at a lower power envelope.

AMD Ryzen 9 7900 Specifications

We haven’t received the 7900X which is the 170W variant of the processor that we’re reviewing here. So we can only compare it with the top-of-the-line 7950X and the mid-range 7600X. Most of the specifications have remained unchanged and we see just the clock speeds having been dropped from 4.7 GHz to 3.6 GHz for the base clock and the turbo clock has been reduced to 5.4 GHz from 5.6 GHz. International pricing is USD 429 which works out to about INR 42,000 with taxes but we don’t have official confirmation from AMD regarding the same. 

  AMD AMD AMD AMD   Socket Codename Foundry Core Process Core Architecture CCD Transistors CCD Die Size I/O Process I/O Die Size tCaseMax Launch Date   Cores - Big Cores - Small Cores Threads Integrated Graphics Integrated Graphics Cores IG Base Frequency IG Turbo Frequency Cache L1 Cache L2 Cache L3 Base Clock Base Multiplier Unlocked Multiplier Big Core Base Frequency Big Core Turbo Clock Small Core Base Frequency Small Core Turbo Clock Memory Type Support Max Memory Capacity Rated Memory Clock Speed Memory Channel Support ECC Memory Support PCIe Gen PCIe Lanes from CPU TDP

Ryzen 9 7950X	Ryzen 9 7900X	Ryzen 9 7900	Ryzen 5 7600X
AM5	AM5	AM5	AM5
Raphael	Raphael	Raphael	Raphael
TSMC	TSMC	TSMC	TSMC
5 nm	5 nm	5 nm	5 nm
Zen 4	Zen 4	Zen 4	Zen 4
6500 mil	6500 mil	6500 mil	6500 mil
70 mm2	70 mm2	70 mm2	70 mm2
6 nm	6 nm	6 nm	6 nm
122 mm2	122 mm2	122 mm2	122 mm2
95°C	95°C	95°C	95°C
27-Sep-2022	27-Sep-2022	9-Jan-2023	27-Sep-2022
16	12	12	6
16	12	12	6
0	0	0	0
32	24	24	12
RDNA2	RDNA2	RDNA2	RDNA2
2	2	2	2
400 MHz	400 MHz	400 MHz	400 MHz
2200 MHz	2200 MHz	2200 MHz	2200 MHz
64K Per Core	64K Per Core	64K Per Core	64K Per Core
1M Per Core	1M Per Core	1M Per Core	1M Per Core
64 MB	64 MB	32 MB	32 MB
100 MHz	100 MHz	100 MHz	100 MHz
45x	47x	36x	47x
Yes	Yes	Yes	Yes
4.5 GHz	4.7 GHz	3.6 GHz	4.7 GHz
5.7 GHz	5.6 GHz	5.4 GHz	5.3 GHz
NA	NA	NA	NA
NA	NA	NA	NA
DDR5	DDR5	DDR5	DDR5
128 GB	128 GB	128 GB	128 GB
5200 MT/s	5200 MT/s	5200 MT/s	5200 MT/s
Dual-Channel	Dual-Channel	Dual-Channel	Dual-Channel
No	No	No	No
5	5	5	5
24	24	24	24
170 W	170 W	65 W	105 W

As with the core configuration, even the GPU configuration has remained unchanged. All processors falling under the Ryzen 7000 family will have inbuilt graphics capabilities and instead of getting a really old GPU architecture, we’re getting RDNA 2 IGP Cores in all four processors. The Ryzen 9 7900 also features 2 RDNA 2 cores with a base clock of 400 MHz and a peak clock of 2200 MHz. 

AMD RYZEN 9 7900 PERFORMANCE

We've kept most of the configuration the same as in the previous reviews. The only difference is the motherboard which has been swapped out for another review unit.

We tested the AMD Ryzen 9 7900 on the following test configuration:

AMD RYZEN TEST RIG
CPU: AMD Ryzen 9 7900
Motherboard: ASUS ROG STRIX X670E-E GAMING WIFI
SSD: WD SN850 1TB NVMe SSD
HDD: Seagate FireCuda 2 TB ST2000DX002
RAM: 2x 16 GB Kingston FURY DDR5 @5200 MT/s
Cooler: Deepcool 280mm AIO
PSU: Cooler Master MWE 850W V2

Cinebench R23

The AMD Ryzen 9 7900 scored 1968 points in the single-threaded run and 25354 points in the multi-threaded run. The single-threaded score is barely lower than the 1997 points that the more powerful 7950X had scored so this 65W part is already looking out to be impressive. As for the multithreaded score, it's way below the 7950X as well as the 13900K.

Blender

In Blender, the AMD Ryzen 9 7900 scores quite lower than the AMD Ryzen 9 7950X and the Intel Core i9-13900K. However, on the basis of time taken to finish renders, it's quite a good processor for 3D modelling workloads. 

AI Benchmark

In the AI benchmark, we see that the AMD Ryzen 9 7900 is very much in line with the AMD Ryzen 9 7950X. 

Memory Latency

We noticed some noticeable differences in the L1 Cache access speeds and latency between the AMD Ryzen 9 7900 and the AMD Ryzen 9 7950X. A similar behaviour could be seen with the L2 cache as well. The difference in performance wasn't as pronounced in the L3 cache tests.

7-Zip

7-Zip is known for regular updates which leverage the latest features that processors tend to incorporate. This gives us a good picture of how each new generation of processors handles compression and decompression of data. 

Gaming

In gaming, we noticed that the AMD Ryzen 9 7900 performs a little better than the Ryzen 5 7600X. Without PBO or Precision Boost Overdrive, it lags behind the Intel Core i5-13600K but with PBO turned on, it nudges a little ahead of the 13600K.

Power consumption

And now, onto what most people would want to know regarding a 65W part. During consistent load conditions, the AMD Ryzen 9 7900 consumes about 82-92 watts which is quite good compared to the 7950X which would easily hit twice that amount. We're talking about video transcoding workloads and synthetic benchmarks such as Cinebench R23.

Temperatures

Peak load temperatures were about 86 degrees celsius which were primarily achieved in synthetic benchmarks. With video transcoding and 3D modelling workloads, the peak temperatures hovered in the mid-70s.

Verdict

The AMD Ryzen 9 7900X is a great processor for folks wanting to build a jack-of-all-trades PC. It's good at gaming, content creation and daily productivity workloads. With the introduction of the new chipsets, the overall platform cost has come down by quite a bit but we still haven't seen an A6XX chipset in the budget segment so things are still a little pricey compared to the competition. That said, the AMD Ryzen 9 7900X is a good performer. All we need to see is whether the Indian pricing helps it retain the same value-for-money proposition as international markets.