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| System Name | HTPC whhaaaat? |
|---|---|
| Processor | 2600k @ 4500mhz |
| Motherboard | Asus Maximus IV gene-z gen3 |
| Cooling | Noctua NH-C14 |
| Memory | Gskill Ripjaw 2x4gb |
| Video Card(s) | EVGA 1080 FTW @ 2037/11016 |
| Storage | 2x512GB MX100/1x Agility 3 128gb ssds, Seagate 3TB HDD |
| Display(s) | Vizio P 65'' 4k tv |
| Case | Lian Li pc-c50b |
| Audio Device(s) | Denon 3311 |
| Power Supply | Corsair 620HX |
A fairly clear picture is starting to emerge about 28nm and voltage in terms to laymen and regular cooling.
At stock 1.15v, the only review I saw that didnt use CCC to overclock achieved 1165mhz. AMD mentioned to them 1200 could be possible at stock, ~1300mhz with voltage tuning.
VR-zone using 1.25v achieved an exactly linear increase.
1700mhz was 1.7v right? Also pretty linear.
That crazy 1335mhz part would then infer a voltage of around 1.31-1.32.
things to note:
1. AMD used ~1.31-1.32v stock for 4890 on 55nm...see point #2. One can always assume they would have wanted the same for 40nm had it not been leaky as hell above ~1.175v (6870/6970 stock voltage). AMD has shown a pattern of being conservative on stock voltage by about 5% on first-gen parts on a process...re 4870/5770/5870. The 3000 series is an anomaly because of the lack of decap layer...hence why yields were so good. Voltage was high...clockspeed not.
2. Intel suggests not running chips above 1.325v, as it has been shown to shorten lifespan of their cpus. AMD may agree with this given their past voltage settings, guidance on 7970 overclocking, and that Sapphire pushed-to-the-max model. This also may get VERY close to the 300W spec.
Now, TSMC aint Intel, and 28nm hkmg clearly aint 40 or 55nm...but rules of thumb are nice...and 28nm looks to put things back on course of where they should be in accordance to the AMD strategy of small dies with topped out voltages and clockspeeds while staying within tdp specs. Because it appears so well organized, I would be very surprised if the fastest and highest voltage official tahiti sku we see is 925mhz @ 1.15v.
I admire all the facets the ATi group looks at when designing a GPU. Thrifty, practical scaling...just damn smart engineering.
At stock 1.15v, the only review I saw that didnt use CCC to overclock achieved 1165mhz. AMD mentioned to them 1200 could be possible at stock, ~1300mhz with voltage tuning.
VR-zone using 1.25v achieved an exactly linear increase.
1700mhz was 1.7v right? Also pretty linear.
That crazy 1335mhz part would then infer a voltage of around 1.31-1.32.
things to note:
1. AMD used ~1.31-1.32v stock for 4890 on 55nm...see point #2. One can always assume they would have wanted the same for 40nm had it not been leaky as hell above ~1.175v (6870/6970 stock voltage). AMD has shown a pattern of being conservative on stock voltage by about 5% on first-gen parts on a process...re 4870/5770/5870. The 3000 series is an anomaly because of the lack of decap layer...hence why yields were so good. Voltage was high...clockspeed not.
2. Intel suggests not running chips above 1.325v, as it has been shown to shorten lifespan of their cpus. AMD may agree with this given their past voltage settings, guidance on 7970 overclocking, and that Sapphire pushed-to-the-max model. This also may get VERY close to the 300W spec.
Now, TSMC aint Intel, and 28nm hkmg clearly aint 40 or 55nm...but rules of thumb are nice...and 28nm looks to put things back on course of where they should be in accordance to the AMD strategy of small dies with topped out voltages and clockspeeds while staying within tdp specs. Because it appears so well organized, I would be very surprised if the fastest and highest voltage official tahiti sku we see is 925mhz @ 1.15v.
I admire all the facets the ATi group looks at when designing a GPU. Thrifty, practical scaling...just damn smart engineering.
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