Generally Gigabyte uses red PCB’s for
all their ATI based graphics products, while the NVIDIA
cards all feature a blue PCB. However, in order to quickly
move their GeForce 7800 GTX parts to the market, they stuck
with the old school green. The size and design of the
GeForce 7800 GTX is much the same as that of the GeForce
6800 Ultra, in fact the only real change appearance wise is
the reference cooling design. The two Gigabyte GeForce 7800
GTX cards that I received look identical to that of the
reference design and while it still does look impressive, it
is nothing out of the ordinary. The packaging on the other
hand looks quite impressive and unlike the ridiculously
large boxes Gigabyte used for their previous generation ATI
and NVIDIA cards, this one is quite reasonable in size.
The GeForce 7800 GTX core consists of
more than 300 million transistors and is manufactured using
a 0.11-micro process. Despite featuring such a complex core
the GeForce 7800 GTX is still clocked higher than its
predecessor. The total number of Raster Operation units has
not changed, meaning these are still 16 texture sample taken
per cycle. This means games that use large amounts of
textures will not see the GeForce 7800 GTX greatly
outperform the older GeForce 6800 Ultra.
There have been a number of visual
improvements made to the GeForce 7800 GTX. For example, the
additional rendering pipelines will help this product work
with more vibrant color ranges. NVIDIA have officially
stated that the GeForce 7800 GTX will be significantly
faster in HDR modes. The inclusion of Transparent FSAA
rendering mode is another visual quality improvement of the
GeForce 7800 GTX.
Like the GeForce 6800 Ultra, these new
graphics cards still use dual 4-pin molex connectors to draw
additional power. The graphics card itself features the
6-pin PCI Express power connector which requires the adapter
for power supplies that do not feature PCIe connectors. This
adapter is of course supplied with the graphics card and is
designed to draw current from two 4-pin molex connectors
just as the GeForce 6800 Ultra does.
The card features 256MB of onboard GDDR3
memory clocked at 600MHz (1200MHz DDR). These cards utilized
Samsung IC’s (K4J55323QF-GC16) and it would appear that the
majority of GeForce 7800 GTX based cards will use this exact
memory. After some quick research, I have found that these
modules are rated at 1200MHz DDR. This means the memory on
our Gigabyte card is already at its maximum frequency. This
will unfortunately not guarantee that there will be much
overclocking headroom, nevertheless I intend to find out
just how well the memory does overclock.
Whilst in action the Gigabyte GeForce
7800 GTX operating volume level is quite pleasant and should
not be any cause for concern. Given how powerful these
graphics cards are I was very surprised to find such a small
and quiet cooling arrangement. Though when running at full
throttle these graphics cards tend to get quite hot,
particularly when in SLI mode. The cards would often rise
just above 80 degrees, creating a very large hot spot within
the case.
Although the operating volume is not
something I would concern myself with, the power requirement
for these graphics cards in SLI is. Originally I tried to
set the GeForce 7800 GTX cards up in SLI using a 460w
Thermaltake PurePower power supply on the Intel nForce4
platform, this configuration would randomly turn off. The
same problem occurred with a 480watt Antec TruePower supply.
The Intel Pentium 4 nForce4 platform required an Antec
550watt power supply to achieve absolute stability.
The AMD Athlon 64 platform was able to
get away with the 460w Thermaltake PurePower power supply
without any problems, which was quite surprising. While it
is true that the Athlon 64 platform does require less power,
the difference in power requirements between the two
platforms is not huge. Nevertheless, I did find the Athlon
64 platform more user friendly with the Gigabyte GeForce
7800 GTX graphics cards in SLI and therefore I used this
system for the testing phase.
The rear of the GeForce 7800 GTX
features an S-Video port supporting the Video-In/Video-Out
function and dual DVI outputs. There are also a number of
cables supplied with the card which will help the user
utilize some of these features. However I will talk about
these cables in an upcoming section of this review. Overall,
the GeForce 7800 GTX looks to be a quality product with many
unique aspects.
