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光驱越慢，用硬盘后提升越大，这是常识

READY BOOST 用在2G以下的系統，性能提升比較明顯

原來2G系統完爆4G內存的PC

[ 本帖最后由 村上春樹 于 2011-8-31 14:21 编辑 ]

免責聲明: 注意以下引用的資料本人沒有相關的專業知識去分辯.大家只作參考看過就算吧。bd是普遍資料說的每倍速36mbps還是54mbps我不知道, 不過有點可以確認的是12倍速dvd的最高速度128mbps只有在讀取光碟最外圍資料時才有。 (之前用英文時好像有人把它當作原文了)!

以下簡略翻譯意思, 若認為有誤或扭曲歡迎提出更正。

http://forum.teamxbox.com/showthread.php?t=447464&page=31#
First of all, Blu-Ray specifications are CLV. DVD spec is CAV. You therefore cannot even compare the two specifications in the first place and in NO way can you conclude that the performance will be "less than half" by using the maximum number of a constant angular drive. That is absurd. "

Besides, the minimum spec for Blu-Ray is 54mbps read speed for a BD-ROM. There is some confusion because a 1X data speed has been spec'd at 36.5mbps which is supposed to be for recordable media. Remember, the minimum read speed required by BD drives for BD-ROM is 54mbps, and this is a CLV drive. This is common knowledge. Any confusion comes from minimum read speeds for data recordables, but the experts are not confused: http://biz.gamedaily.com/industry/interview/?id=10603
Either way, since your DVD specification is constant angular velocity, you're comparison defines the saying "apples and oranges." You are in effect taking the absolute best performance of the DVD drives, found only on the outer diameter of the physical disc, and comparing it to a specification which is constant no matter where the data is located. The real world performance will not be "half" unless you are talking about a few megabytes on the outer rim of the DVD... the transfer rate dropoff from that point goes all the way to 8.2 MB/s. The majority of data on a DVD 12X drive will be transferred at the mean area, which is a little over 12 MB/s(發文者好像筆誤了,該是16MB/s), whereas the BD transfer rate, even at your data spec, will always be around 9 MB/s no matter what. And if experts like the VP of Sonopress are to be believed, someone in charge of technology at one of the largest disc manufacturing firms in the world, along with taking into account that we know the minimum max read speed for consumer BD drives for BD-ROM will be 54Mbps (the 2X read specification would therefore be 108Mbps), then at 2X that is a little over 13 MB/s. This would actually be CONSISTENTLY FASTER than a DVD constant angular drive at 12X in all but the most outer rims of the DVD.

很多人對bd的速度有所誤解, 36.5mbps只是1倍速bd可寫入媒體的速度。  blu-ray光驅最基本的讀取速度要求是 54mbps。
12倍速的dvd最外圍資料傳送速度為12MB/s多點, 但這速度到內圈時會跌到約8.2MB/s. 而2倍bd就是用72mbps計算, 不管從碟上那處讀取也能保持一直保持約9mb/s的速度1 [: n7 G5 A: A' ?
若用108mbps計更能比達到13MB/s多點, 基本上比12倍dvd為快, 除了dvd在讀取最外圈的資料時。
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這是文中的連結http://biz.gamedaily.com/industry/interview/?id=10603
內容是對全球其中一間最大的多媒體企業Sonopress(http://195.71.127.123/index.php?id=720) (對hddvd和bd都支持的企業), 科研部副總裁Peter Schaper的專訪
在此只引用關鍵部份
BIZ: What are the likely Blu-ray player speeds at launch, knowing that movie playback is 1.5x of "reference velocity"? What speed would a 2x Blu-ray
drive transfer data at? 72Mbs or 108Mbs? 2倍速的bd資料傳送速度是多少

PS: 108 Mbs.;

Either way, at either spec, this in no way can be interpreted to translate to "less than half" of the real world performance, especially since in the real world the only reason to compare read speeds is load times, and not only can you not compare load times of the maximum data rate of a constant angular drive versus a constant linear one, let alone red flag yourself by comparing the MAXIMUM transfer rate of a constant angular drive against a CLV which is totally absurd, you also can't compare "load times" during gaming of a console with a standard hard drive versus one without. Either way we'll have to wait and see when games are actually out.

這裡主要說ps3和360都有 hdd, 所以只比光驅讀取速度沒什麼意思4 x1 ~(
實際遊戲時的再計算讀取時間更實際


再加多點個人看法： 對bd是不是能不管資料在光碟的那裡都能恆速成疑(因為本人不知CLV和CAV是什麼), 但很同出了遊戲再看讀取時間更實際。 另外在Peter Schaper的專訪中也提及其實bd和hd dvd的成本差距沒toshiba說的那麼多。

[ 本帖最后由 leon2510 于 2011-8-31 14:41 编辑 ]

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2倍bd是72，蓝光播放视频不是一倍速，是1.5倍速，即54
其实看实际就行了，ps3和360垮平台游戏又不是没有，大家都不安装的比一下即可

引用:

原帖由 村上春樹 于 2011-8-31 14:00 发表


你急著說明當乞丐好，怎麼回事呢

我有10塊我只會去買飲料，乞丐有十塊就去買饅頭過一天了，他這樣就吃飽我還沒呀了。

当乞丐的是360啊，完全安装都全救济了，结果效果还是一般，可见基础多么差劲了。

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另外dvd单倍是1350k，12倍要16兆了，谁说是才12兆多？

引用:

原帖由 tdka 于 2011-8-31 14:12 发表
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光驱越慢，用硬盘后提升越大，这是常识

在硬盘差别不大的情况下，光驱+硬盘居然完胜单硬盘，真尴尬，如果光驱过慢肯定要拖累硬盘，可惜事实相反。

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引用:

原帖由 @zhangjingy2008  于 2011-8-31 14:49 发表
当乞丐的是360啊，完全安装都全救济了，结果效果还是一般，可见基础多么差劲了。

效果一般是指什么，莫非比ps3版慢？

引用:

原帖由 tdka 于 2011-8-31 14:50 发表
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效果一般是指什么，莫非比ps3版慢？

提升的秒数完败给PS3，上面列出了很多大于6G的游戏数据。

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引用:

原帖由 @zhangjingy2008  于 2011-8-31 14:50 发表
在硬盘差别不大的情况下，光驱+硬盘居然完胜单硬盘，真尴尬，如果光驱过慢肯定要拖累硬盘，可惜事实相反。

求完胜数据
另外数据是并行读取，光驱再慢也不会拖硬盘后腿

引用:

原帖由 tdka 于 2011-8-31 14:49 发表
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另外dvd单倍是1350k，12倍要16兆了，谁说是才12兆多？

那是读取D5，对于360的12X光驱，读取D9封顶才8X。

引用:

原帖由 tdka 于 2011-8-31 14:53 发表
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求完胜数据
另外数据是并行读取，光驱再慢也不会拖硬盘后腿

你的意思MS傻到浪费硬盘不说，效果还不如光驱+硬盘，233MAX，MS果然是渣。

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引用:

原帖由 @zhangjingy2008  于 2011-8-31 14:53 发表
提升的秒数完败给PS3，上面列出了很多大于6G的游戏数据。

光驱慢提升大，没问题啊

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引用:

原帖由 @zhangjingy2008  于 2011-8-31 14:56 发表
你的意思MS傻到浪费硬盘不说，效果还不如光驱+硬盘，233MAX，MS果然是渣。

不需要啊，此时光驱就不工作了，而且速度也很快，比如gta4，比ps3版强制安装后还快

看了看LENS的数据，两版本都不安装的情况下，跨平台游戏多数读盘差距不大，顶多2秒，而一些游戏的PS3版本光盘容量更大，支持更高级别的音效。