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AMD Ryzen 9 7900

W1zzard

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With the Ryzen 9 7900, AMD is offering a more affordable version of their powerful 12-core processor. Our review confirms that the performance difference to the 7900X is small, yet the 7900 non-X consumes less than half the power compared to its big brother.

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Efficiency and power consumption is outstanding, but otherwise for the performance that you get, pretty meh to be honest, plus somehow the normal 7900X is a bit cheaper than this and faster in applications....
 
Since the 7900 is brand new, it costs more at the moment than 7900X. Might as well get the X and use it in ECO mode for the same wattage and performance as nonX.
 
Would be good to get a review of some non-K Raptor Lakes for comparison.
 
A terribly good CPU, shame price doesn't help it...
 
I wonder what's the power / heat if you disable CPB and PBO? There was a test at puget systems where they got ~95% performance but a 30C drop in temperature.
Seeing that the 7900 is 3.7 GHz and the 7900X is 4.7 GHz by default, that's one place where the 7900X would be much better.
 
A terribly good CPU, shame price doesn't help it...
Depends how you look at it. It's generally cheaper than the 5950X with the same MT performance, better ST and better efficiency. Only drawback being the platform price.
 
Interesting. As an owner of the X3D version of this chip it seems that the only thing that V cache adds is about 11 watts as I have not seen my chip go past 87 Watts. The price is actually good and as for vs the X you are getting a chip that has been refined for performance by AMD and not turned up to 11 to compete with Intel in benchmarks. I expect once these chips reach a certain price point that they will sell quite well.

Depends how you look at it. It's generally cheaper than the 5950X with the same MT performance, better ST and better efficiency. Only drawback being the platform price.
Objectively AM5 is no longer more expensive than AM4.
 
  • Long boot times

Not anymore, at least not on my system with the current BIOS, boot times are 5< seconds.
 
Not anymore, at least not on my system with the current BIOS, boot times are 5< seconds.
Which motherboard? ASUS Hero definitely very long, and turning on Memory Context restore causes random bluescreens as soon as you stop the mouse
 
Which motherboard? ASUS Hero definitely very long, and turning on Memory Context restore causes random bluescreens as soon as you stop the mouse

Asrock B650 Pro RS, I had long boot times as well but the latest BIOS fixed them, I haven't exactly timed it but it's something like 5 seconds till the BIOS splash screen and then maybe 5 seconds more till windows loads.
 
costs more than a 7900X? weird! If a 65w or more efficient or lower temp part adds value you'd be better off buying the cheaper X variant and trim its performance/power levels to match the 7900.

I want to see this baby at $375 although can't see AMD discounting any of these models anytime soon... they are a nice door opener to X3D price level support
 
costs more than a 7900X? weird! If a 65w or more efficient or lower temp part adds value you'd be better off buying the cheaper X variant and trim its performance/power levels to match the 7900.

7900 also comes with a cooler.
 
Asrock B650 Pro RS, I had long boot times as well but the latest BIOS fixed them, I haven't exactly timed it but it's something like 5 seconds till the BIOS splash screen and then maybe 5 seconds more till windows loads.
My boot times are less than 20 sec from power button to Windows login on an Asrock 650e steel legend with a 7700X. I have the latest bios and EXPO optimized ddr5 5600 from Corsair. I’m going to say thats ‘normal’ boot time.
 
7900 also comes with a cooler.

honestly i see now value in stock coolers for these 12c/24t Zen 4 parts. Maybe a nice treat for someone on a super tight budget but IMO if you're going for a 7900 unleash its full potential with an aftermarket cooler. Personally i can't stand noisy coolers either.
 
Asrock B650 Pro RS, I had long boot times as well but the latest BIOS fixed them, I haven't exactly timed it but it's something like 5 seconds till the BIOS splash screen and then maybe 5 seconds more till windows loads.
I also have "not long" boot times with the Asus Tuf B650 ATX, and even quite short times with the Gigabyte B650M DS3H. Asus slower than Gigabyte for sure.
 
Well with PBO Max and OC the 7900 is nothing more then a worse binned 7900X...
The "efficiency" comes solely from a low stock PPT. You can achieve that with any 7x00X CPU...
 
Which motherboard? ASUS Hero definitely very long, and turning on Memory Context restore causes random bluescreens as soon as you stop the mouse
not the first one who being let down by asus. jayz has the same problem
and does not have the problem with an asrock taichi
 
7900X in Eco-mode or tuned and undervolted cost less, delivers more in every category across the board. That Price does not compute at all. o_O
 
In terms of long Boot times there was a notification from Level1 Youtube channel. Apparently if you run EXPO and pick the 1st profile it will do Memory training the first time it boots. If you pick the 2nd profile it will train the memory every time it boots. I am on an Asus X670E E Strix and my Boot times are not noticeably longer than my Previous AM4 system. For me I am totally enjoying the platform and once this chip gets to good price it will be the basis of systems I sell. One thing that has translated to AM5 is that a 12 core CPU will be the smoothest, stablest experience on Windows (for me). What is not fully appreciated is if you buy this chip, anything they release in the next 3 years that is at 65W will just be a straight CPU upgrade.

7900X in Eco-mode or tuned and undervolted cost less, delivers more in every category across the board. That Price does not compute at all. o_O
But you don't get a cooler.
 
If this CPU drops down into the mid/upper $300s, it is a winning product, especially at that power efficiency.
 
In terms of long Boot times there was a notification from Level1 Youtube channel. Apparently if you run EXPO and pick the 1st profile it will do Memory training the first time it boots. If you pick the 2nd profile it will train the memory every time it boots. I am on an Asus X670E E Strix and my Boot times are not noticeably longer than my Previous AM4 system. For me I am totally enjoying the platform and once this chip gets to good price it will be the basis of systems I sell. One thing that has translated to AM5 is that a 12 core CPU will be the smoothest, stablest experience on Windows (for me). What is not fully appreciated is if you buy this chip, anything they release in the next 3 years that is at 65W will just be a straight CPU upgrade.


But you don't get a cooler.
So maybe the secret of AM5 boot times is EXPO. I purposely picked EXPO rated RAM in hopes that it would mitigate long boot times. I might try and change my BIOS settings between EXPO and XMP and see what happens.
 
Which motherboard? ASUS Hero definitely very long, and turning on Memory Context restore causes random bluescreens as soon as you stop the mouse
When I was at Microcenter buying parts for my AMD 7700X build, the sales rep steered me far away from ASUS motherboards. I even suggested that I was entertaining the idea of going with an ASUS motherboard because like others, I thought ASUS was the best brand one could buy. I could tell he was trying very hard to convince me not to buy one. At one point during the conversation, he told me that they were having a lot of returned ASUS motherboards in both the AMD and the Intel camp. It was like he was telling me to avoid them like the plague.

Users on Reddit seem to also be having lots of problems with ASUS motherboards.

I went with a Gigabyte board instead and have had no issues at all.
 
When I was at Microcenter buying parts for my AMD 7700X build, the sales rep steered me far away from ASUS motherboards. I even suggested that I was entertaining the idea of going with an ASUS motherboard because like others, I thought ASUS was the best brand one could buy. I could tell he was trying very hard to convince me not to buy one. At one point during the conversation, he told me that they were having a lot of returned ASUS motherboards in both the AMD and the Intel camp. It was like he was telling me to avoid them like the plague.

Users on Reddit seem to also be having lots of problems with ASUS motherboards.

I went with a Gigabyte board instead and have had no issues at all.
Without looking I bet that the majority of those boards were the Prime series. Of all the budget boards Asus is probably the worst. TUF and Strix should be where to start but that also costs. It would seem that Gigabyte like SK Hynix (DDR5) has really tried hard to separate themselves with AM5. I have not bought a Gigabyte board in Years but i might have to try one when they get a little cheaper.
 
My boot times are less than 20 sec from power button to Windows login on an Asrock 650e steel legend with a 7700X. I have the latest bios and EXPO optimized ddr5 5600 from Corsair. I’m going to say thats ‘normal’ boot time.
Honestly that still isnt great, my 5800x3d build is sub 10 seconds.
 
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