powervr2 limits

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Re: powervr2 limits

Post by BlueCrab » Sun Nov 30, 2014 1:13 am

No, it is not, unless you want something that runs at like 1 frame per second (or less).

The PSP is a more powerful piece of hardware than is the Dreamcast, and there's no getting around that.
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Re: powervr2 limits

Post by chao2 » Mon Dec 01, 2014 7:39 pm

I find that pretty surprising thinking a couple years afters the cancellation of the dreamcast a handheld already had surpassed it. The psp entered the market around 2003 and the dreamcast left in 2001. Isn't the dreamcast about half the power of a ps2?
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Re: powervr2 limits

Post by BlueCrab » Tue Dec 02, 2014 12:24 am

The PSP was released in Japan in 2004 (2005 everywhere else). That said, remember, the Dreamcast was released in 1998. Looking at the cycles of video game hardware, it's not really that hard to believe that the PSP is more powerful than the Dreamcast. Remember, the Sega Saturn was released in 1994 in Japan. I think we can all agree that the Dreamcast is vastly more powerful than the Saturn and it was only released 4 years later. :wink:

Hell, looking at raw stats, there's no comparison. The PSP's CPU runs at 333 MHz (vs 200 MHz on the Dreamcast), and is otherwise comparable in the instruction execution speed and such. Plus, the PSP has double (or quadruple on the later models) the RAM of the Dreamcast. Also, the PSP's GPU has actual hardware transform/lighting (which the Dreamcast lacks).

The PSP kinda threw down the gauntlet of being much more powerful than any handheld console that came before it.
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Re: powervr2 limits

Post by Chilly Willy » Tue Dec 02, 2014 5:14 pm

Yeah, PSP was fun to play with. I'll probably get back to more PSP stuff next year. It was a POWERFUL little handheld.
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Re: powervr2 limits

Post by chao2 » Tue Dec 02, 2014 8:42 pm

So in terms of power the 6th gen would look like this: xbox>gamecube>ps2>psp>dreamcast


How much more powerful is the ps2 compared to the psp and dreamcast?
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Re: powervr2 limits

Post by Christuserloeser » Wed Dec 03, 2014 8:26 am

I am not sure how much more advanced PS2 really is. Many PS2 games render internally at resolutions like 320x480 or 640x240 (see DOA 2 Xtreme vs Dead or Alive 2 on Dreamcast) instead of true 640x480 like Dreamcast does.


btw NAOMI is identical to Dreamcast - aside of the differences in RAM.
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Re: powervr2 limits

Post by hilltopper06 » Wed Dec 03, 2014 10:58 am

chao2 wrote:So in terms of power the 6th gen would look like this: xbox>gamecube>ps2>psp>dreamcast


How much more powerful is the ps2 compared to the psp and dreamcast?
The PSP was not part of that gen.

1.) It is a portable, not a console.

2.) It was release in North America in 2005, the same calendar year as the Xbox 360.

It is not comparable to a Dreamcast that was released in 1999.

As far as raw power, I would say XBOX/GC > PS2 > DC. There are some things the DC did better than the PS2, but overall the PS2 was a more powerful console than the DC. The XBOX and GC were roughly equal.
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Re: powervr2 limits

Post by chao2 » Sat Dec 06, 2014 10:05 pm

Image




Would a dreamcast version of these games look anywhere close visually?



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Re: powervr2 limits

Post by Lander » Sun Dec 07, 2014 5:34 pm

I think a dreamcast version of resident evil 4 would look similar to house of the dead 2.
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Re: powervr2 limits

Post by Neoblast » Mon Dec 08, 2014 8:46 am

Ps2 stayed longer. Sega didn't squeeze the dreamcast as much as developers did on the sony system.

I think it would be close to some ps2 ports. Perhaps with some tricks it might look better in some occasions. Since the textures on the dc look much better in comparison. That and antialiasing.
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Re: powervr2 limits

Post by RyoDC » Fri Dec 12, 2014 3:34 am

Well, Dreamcast system has some specific hardware features, yielding which, better performance may be achieved at some stages of the pipeline (for example, Dreamcast has the Tile Accelerator, which PS2 lacks, taking advantage of this concrete feature may gain some good results, or, for example, advanced filtering - you can set framebuffer in Dreamcast to be 2 times wider than the screen resolution, so the hardware can take two adjacent pixels and interpolate the value between them, resulting into a more sleek image, that is, hardware anti-aliasing, which is better then in PS2).
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Re: powervr2 limits

Post by bogglez » Mon Dec 15, 2014 7:56 am

Earlier I said the PS2 can probably read DVDs faster than the DC can read GDs, but it turns out to be wrong.. So while the DC has less memory available for a cache, it can read data more quickly. So streaming assets should be roughly equally possible.
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Re: powervr2 limits

Post by RyoDC » Mon Dec 15, 2014 12:01 pm

So while the DC has less memory available for a cache
I can't proof my point with a slides or some other info but I recall that I've seen a diagram that shows that bigger cache sizes doesn't necessarily mean boost up.
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Re: powervr2 limits

Post by bogglez » Mon Dec 15, 2014 1:25 pm

RyoDC wrote:
So while the DC has less memory available for a cache
I can't proof my point with a slides or some other info but I recall that I've seen a diagram that shows that bigger cache sizes doesn't necessarily mean boost up.
If the cache for streaming assets is bigger, one needs to read files from disc less. So the smaller the cache, the more often one needs to read, which means the reading speed needs to be faster.
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Re: powervr2 limits

Post by chao2 » Mon Dec 15, 2014 9:43 pm

I was on the sega 16 forums a little while ago and I was reading this ps2 vs Dreamcast thread where a former developer on both of the consoles stumbled on. He gave some interesting info about the dreamcast and goes by the username Rusty and wishes he had more time to work on it. He knew someone who had version 5 dev kits, with SCSI cards and GR-ROM emulators. He also mentioned he really loved to write a streaming open-world game on the dreamcast. He appears on page 24 http://www.sega-16.com/forum/showthread ... ics/page25
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Re: powervr2 limits

Post by RyoDC » Fri Sep 18, 2015 3:59 am

RyoDC wrote:
So while the DC has less memory available for a cache
I can't proof my point with a slides or some other info but I recall that I've seen a diagram that shows that bigger cache sizes doesn't necessarily mean boost up.
If the cache for streaming assets is bigger, one needs to read files from disc less. So the smaller the cache, the more often one needs to read, which means the reading speed needs to be faster.
I found an article that proves my point, sorry for necroposting.
http://superuser.com/a/72217/253214

Also, cache efficiency heavily depends on algorithm and data structure:
The proportion of accesses that result in a cache hit is known as the hit rate, and can be a measure of the effectiveness of the cache for a given program or algorithm.
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Re: powervr2 limits

Post by bogglez » Thu Sep 24, 2015 12:19 pm

RyoDC wrote:
RyoDC wrote:
So while the DC has less memory available for a cache
I can't proof my point with a slides or some other info but I recall that I've seen a diagram that shows that bigger cache sizes doesn't necessarily mean boost up.
If the cache for streaming assets is bigger, one needs to read files from disc less. So the smaller the cache, the more often one needs to read, which means the reading speed needs to be faster.
I found an article that proves my point, sorry for necroposting.
http://superuser.com/a/72217/253214
On this forum that's not necroposting yet :P
The stackoverflow comment refers to a cache on the CPU. The speed difference between L1 vs L2 is miniscule compared to access to RAM vs disc, so the argument doesn't hold. (BTW L1 cache is just too expensive, that's the bigger reason at play there).
Imagine you have a 700MB cache in RAM and as you read content from the disc it is stored there. Eventually all of the CD content is in the cache, although the order will be different.
By using the cache, instead of reading from the disc, you would always read from RAM. Even if it took you a long time to find the data in the cache due to the changed order, accessing the disc is so slow in comparison (magnitudes!), that you're guaranteed to get a speedup.
Also, cache efficiency heavily depends on algorithm and data structure:
The proportion of accesses that result in a cache hit is known as the hit rate, and can be a measure of the effectiveness of the cache for a given program or algorithm.
Yes, but that's the case for both PS2 and DC. Even the best algorithm will benefit from a larger cache. Once the algorithm needs to read from disc, it's game over. A bad algorithm with a larger cache will beat a smart algorithm with a small cache (again, due to the huge read speed difference between RAM and disc).
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Re: powervr2 limits

Post by RyoDC » Sun Nov 08, 2015 5:54 am

By using the cache, instead of reading from the disc, you would always read from RAM. Even if it took you a long time to find the data in the cache due to the changed order, accessing the disc is so slow in comparison (magnitudes!), that you're guaranteed to get a speedup.
Of course, of course, this is clear, I was arguing the "the bigger cache the better" argument more, not reading from the disk :)
it's game over. A bad algorithm with a larger cache will beat a smart algorithm with a small cache (again, due to the huge read speed difference between RAM and disc).
Well, of course, if talking about reading data directly from the disk.

I was thinking more about algorithms that have all needed data in lower level cache (l2-L3) or ram for example.
That extra cache size will kill the performance because of lookup latency, that was my point.
And if you have first order cache that large of the optical drive size, the whole point of such a cache will be zero, because lookup latency will be that big, that it will degrade down to RAM access times or even slower.

But yes, I think you're right in a whole, that reading from disk in thousand times slower then even read from RAM and even big cache latency will be magnitudes smaller then time to read int from the optical disk.

But using first order cache of size 700 MBs is unnecessary overkill that will destroy the purpose of cache totally:)
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Re: powervr2 limits

Post by chao2 » Wed Dec 02, 2015 9:41 pm

Does anyone know how much programming tricks and software that never came to the dreamcast?
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Re: powervr2 limits

Post by RyoDC » Sun Dec 20, 2015 4:36 am

>how much programming tricks

It's hard to answer this question. Probably, many? How many was invented in the past years?

>and software that never came to the dreamcast?

There's a list on wikipedia somewhere. I think it will be quite useful.

http://www.tomshardware.co.uk/forum/324 ... cast-games
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