Sidebar Sidebar
Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Zombieload: I5 or I9 iMac 2019?

Z

Zettie1996

macrumors newbie
Original poster
May 15, 2019
12
4
Utrecht
Hi all,
I'm looking to buy my first iMac. Besides the 2 extra cores in in the i9 vs the i5 are there more reasons to choose the i9 now that hyperthreading should be switched off for the Zombieload patch?
If no, my choice will be i5, vega48 and 1TB ssd :). My other choice was a smaller ssd (512GB), vega48 and an i9.
 
Yes, from that update ( https://support.apple.com/nl-nl/HT210107 ):
Although there are no known exploits affecting customers at the time of this writing, customers with computers at heightened risk or who run untrusted software on their Mac can optionally enable full mitigation to prevent harmful apps from exploiting these vulnerabilities. Full mitigation requires using the Terminal app to enable an additional CPU instruction and disable hyper-threading processing technology. This capability is available for macOS Mojave, High Sierra, and Sierra in the latest security updates and may reduce performance by up to 40 percent2, with the most impact on intensive computing tasks that are highly multithreaded. Learn how to enable full mitigation.
 
i9 has 8 cores and 8 threads even with Hyperthreading turned off. i9 also has a 16MB SmartCache.

I don’t plan to turn off Hyperthreading or worry too much about these exploits. I’ll just keep it up to date and maybe be a little more cautious about what software I run and it’s origin.
 
  • Like
Reactions: codernova
Zettie1996 said:
Yes, from that update ( https://support.apple.com/nl-nl/HT210107 ):
Although there are no known exploits affecting customers at the time of this writing, customers with computers at heightened risk or who run untrusted software on their Mac can optionally enable full mitigation to prevent harmful apps from exploiting these vulnerabilities. Full mitigation requires using the Terminal app to enable an additional CPU instruction and disable hyper-threading processing technology. This capability is available for macOS Mojave, High Sierra, and Sierra in the latest security updates and may reduce performance by up to 40 percent2, with the most impact on intensive computing tasks that are highly multithreaded. Learn how to enable full mitigation.
Click to expand...

I would not worry about it unless you are turning off SIP and loading up on a lot of unsigned software. Certified Apple Developers who do not sell their apps in the Mac App Store are going to have to at least get their applications notarized, which should provide another layer of security. Not installing Flash or Java reduces two other attack vectors. Keeping the Firewall on and active on your Mac (System Preferences) is another.

I have no doubt that this is not the last exploit of Intel CPUs, but it would not dissuade me from buying the Core i9 if my workload depended on it.
 
  • Like
Reactions: codernova, wardie and kazmac
I decided to return my i9/580X/512GB iMac in order to get one with a Vega 48 GPU and 1TB SSD. I was tempted to still get an i9 but opted for i5 instead. The hyper-threading security concerns were part of my decision but so was hoping that the i5 would run a little cooler than the i9.
 
codernova said:
https://www.intel.com/content/www/us/en/products/processors/core/i9-processors/i9-9900k.html
https://ark.intel.com/content/www/u...-9600k-processor-9m-cache-up-to-4-60-ghz.html

Since both CPUs have the exact same 95 Watt TDP, wouldn't that mean the i9 will run cooler usually? The i9 will take a larger load before maxing out, while the i5 will max out sooner thus hitting its 95 Watt TDP earlier. Also the i5 will take longer to finish the work meaning even more time at max TDP.
Click to expand...

Not sure. Want to try it out and see how it runs compared to the i9 I just had. I wanted to get the i9 but I was already pushing my budget with the 1TB and Vega upgrades that I really wanted too. Too bad the top base model didn’t include the 8-core i7.
 
  • Like
Reactions: codernova
spiderpumpkin said:
Not sure. Want to try it out and see how it runs compared to the i9 I just had. I wanted to get the i9 but I was already pushing my budget with the 1TB and Vega upgrades that I really wanted too. Too bad the top base model didn’t include the 8-core i7.
Click to expand...

I highly doubt any of these top tier 2019 iMac configurations of any variety will disappoint the majority of us. They are all extremely powerful.
 
You must log in or register to reply here.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.
Top Bottom
Back